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Investigation Of The Email Notice Issue In Aleph, Gordon Xu, Yi Chen Jan 2017

Investigation Of The Email Notice Issue In Aleph, Gordon Xu, Yi Chen

Publications and Research

Based on experimental results and existing resources, the paper explored and identified the major contributing factors to the email notice issue, including local administrator status, Aleph client, mail server, Aleph system files, and security settings. The paper elaborated the troubleshooting process, and how to find the solution to the issue. The authors suggested recommendations based the lessons learned from the project experience. The project experience presented in this paper should be instructive for libraries solving the similar problems.


Bulk Viscous Corrections To Screening And Damping In Qcd At High Temperatures, Qianqian Du, Adrian Dumitru, Yun Guo, Michael Strickland Jan 2017

Bulk Viscous Corrections To Screening And Damping In Qcd At High Temperatures, Qianqian Du, Adrian Dumitru, Yun Guo, Michael Strickland

Publications and Research

Non-equilibrium corrections to the distribution functions of quarks and gluons in a hot and dense QCD medium modify the “hard thermal loops” (HTL). The HTLs determine the retarded, advanced, and symmetric (time-ordered) propagators for gluons with soft momenta as well as the Debye screening and Landau damping mass scales. We compute such corrections to a thermal as well as to a non-thermal fixed point. The screening and damping mass scales are sensitive to the bulk pressure and hence to (pseudo-) critical dynamical scaling of the bulk viscosity in the vicinity of a second-order critical point. This could be reflected in …


Schrödinger Theory Of Electrons In Electromagnetic Fields: New Perspectives, Viraht Sahni, Xiao-Yin Pan Jan 2017

Schrödinger Theory Of Electrons In Electromagnetic Fields: New Perspectives, Viraht Sahni, Xiao-Yin Pan

Publications and Research

The Schrödinger theory of electrons in an external electromagnetic field is described from the new perspective of the individual electron. The perspective is arrived at via the time-dependent "Quantal Newtonian" law (or differential virial theorem). (The time-independent law, a special case, provides a similar description of stationary-state theory). These laws are in terms of "classical" fields whose sources are quantal expectations of Hermitian operators taken with respect to the wave function. The laws reveal the following physics: (a) in addition to the external field, each electron experiences an internal field whose components are representative of a specific property of the …


Rules And Mechanisms For Efficient Two-Stage Learning In Neural Circuits, Tiberiu Teşileanu, Bence Ölveczky, Vijay Balasubramanian Jan 2017

Rules And Mechanisms For Efficient Two-Stage Learning In Neural Circuits, Tiberiu Teşileanu, Bence Ölveczky, Vijay Balasubramanian

Publications and Research

Trial-and-error learning requires evaluating variable actions and reinforcing successful variants. In songbirds, vocal exploration is induced by LMAN, the output of a basal ganglia-related circuit that also contributes a corrective bias to the vocal output. This bias is gradually consolidated in RA, a motor cortex analogue downstream of LMAN. We develop a new model of such two-stage learning. Using stochastic gradient descent, we derive how the activity in ‘tutor’ circuits (e.g., LMAN) should match plasticity mechanisms in ‘student’ circuits (e.g., RA) to achieve efficient learning. We further describe a reinforcement learning framework through which the tutor can build its teaching …


Consequences Of Job Stress For The Psychological Well-Being Of Teachers, Irvin Sam Schonfeld, Renzo Bianchi, Peter Luehring-Jones Jan 2017

Consequences Of Job Stress For The Psychological Well-Being Of Teachers, Irvin Sam Schonfeld, Renzo Bianchi, Peter Luehring-Jones

Publications and Research

This chapter examines research on the relationship between job stressors and mental health (depressive symptoms, burnout, and mental disorders such as depression) in teachers. Teachers are exposed daily to job stressors (e.g., student disruptiveness) that have been linked to adverse mental health effects. Epidemiologic research indicates that when compared to members of other groups, teachers experience higher rates of mental disorder, although some studies question that conclusion. Large-scale studies indicate when compared to members of other occupational groups, teachers are at higher risk for exposure to workplace violence, with its adverse mental health consequences. Longitudinal research has linked teaching-related stressors …


Justified True Belief: Plato, Gettier, And Turing, Rohit Parikh, Adriana Renero Jan 2017

Justified True Belief: Plato, Gettier, And Turing, Rohit Parikh, Adriana Renero

Publications and Research

We examine the relationship between the justified true belief (JTB) account of knowledge and Plato’s theory about it as expounded in the Theaetetus. Considering Socrates’ remarks in the Theaetetus brings us to some concerns raised by Turing and to Wittgenstein’s famous comment explanations come to an end somewhere. We present two simple technical results which bear on the question. Finally, we look at the pragmatic aspects of knowledge attributions. In an Appendix we say a few words about Indian epistemology and Gettier problems.


How To Support Online Research And Comprehension In The Content Areas, Jennifer Van Allen Jan 2017

How To Support Online Research And Comprehension In The Content Areas, Jennifer Van Allen

Publications and Research

College and career readiness requires our students to use new technologies to locate information, critically evaluate and analyze that information, collaborate and connect with others, produce and share information, and achieve personal, professional, and academic goals. The purpose of this paper is to describe online research and comprehension skills of successful Internet readers and make two practical recommendations, using a social studies and mathematics context, for incorporating these skills in the content areas. Content area teachers can help students create a word bank to identify relevant discipline specific information and use a think aloud process consisting of modeling, guided practice, …


Bioremoval Of Phenol From Aqueous Solutions Using Native Caribbean Seaweed, Abel E. Navarro, Anibal Hernandez-Vega, Md Emran Masud, Loretta M. Roberson, Liz M. Diaz-Vázquez Dec 2016

Bioremoval Of Phenol From Aqueous Solutions Using Native Caribbean Seaweed, Abel E. Navarro, Anibal Hernandez-Vega, Md Emran Masud, Loretta M. Roberson, Liz M. Diaz-Vázquez

Publications and Research

Among several Puerto Rican algae, Sargassum sp. (SG) and Chaetomorpha (CM) showed the highest phenol adsorption capacity from aqueous solutions and were used in optimized adsorption batch experiments at room temperature. The effects of pH, adsorbent dose, phenol concentration, salinity and presence of interfering substances were evaluated. Initial solution pH exhibited a strong effect, mainly on the phenol aqueous chemistry; showing the maximum adsorption at pH 10. Sorption isotherm results were modelled according to the Langmuir, Tempkin and Freundlich equations. Isotherm modelling indicated a maximum adsorption capacity (qmax) of 82.10 and 17.7 mg of phenol per gram of SG and …


A Machine Learning Approach For Using The Postmortem Skin Microbiome To Estimate The Postmortem Interval, Hunter R. Johnson, Donovan D. Trinidad, Stephania Guzman, Zenab Khan, James V. Parziale, Jennifer M. Debruyn, Nathan H. Lents Dec 2016

A Machine Learning Approach For Using The Postmortem Skin Microbiome To Estimate The Postmortem Interval, Hunter R. Johnson, Donovan D. Trinidad, Stephania Guzman, Zenab Khan, James V. Parziale, Jennifer M. Debruyn, Nathan H. Lents

Publications and Research

Research on the human microbiome, the microbiota that live in, on, and around the human person, has revolutionized our understanding of the complex interactions between microbial life and human health and disease. The microbiome may also provide a valuable tool in forensic death investigations by helping to reveal the postmortem interval (PMI) of a decedent that is discovered after an unknown amount of time since death. Current methods of estimating PMI for cadavers discovered in uncontrolled, unstudied environments have substantial limitations, some of which may be overcome through the use of microbial indicators. In this project, we sampled the microbiomes …


Generation Of Flower High-Order Poincaré Sphere Laser Beams From A Spatial Light Modulator, T. H. Lu, T. D. Huang, J. G. Wang, L. W. Wang, Robert R. Alfano Dec 2016

Generation Of Flower High-Order Poincaré Sphere Laser Beams From A Spatial Light Modulator, T. H. Lu, T. D. Huang, J. G. Wang, L. W. Wang, Robert R. Alfano

Publications and Research

We propose and experimentally demonstrate a new complex laser beam with inhomogeneous polarization distributions mapping onto high-order Poincaré spheres (HOPSs). The complex laser mode is achieved by superposition of Laguerre-Gaussian modes and manifests exotic flower-like localization on intensity and phase profiles. A simple optical system is used to generate a polarization-variant distribution on the complex laser mode by superposition of orthogonal circular polarizations with opposite topological charges. Numerical analyses of the polarization distribution are consistent with the experimental results. The novel flower HOPS beams can act as a new light source for photonic applications.


A New Operational Snow Retrieval Algorithm Applied To Historical Amsr-E Brightness Temperatures, Marco Tedesco, Jeyavinoth Jeyaratnam Dec 2016

A New Operational Snow Retrieval Algorithm Applied To Historical Amsr-E Brightness Temperatures, Marco Tedesco, Jeyavinoth Jeyaratnam

Publications and Research

Snow is a key element of the water and energy cycles and the knowledge of spatio-temporal distribution of snow depth and snow water equivalent (SWE) is fundamental for hydrological and climatological applications. SWE and snow depth estimates can be obtained from spaceborne microwave brightness temperatures at global scale and high temporal resolution (daily). In this regard, the data recorded by the Advanced Microwave Scanning Radiometer—Earth Orbiting System (EOS) (AMSR-E) onboard the National Aeronautics and Space Administration’s (NASA) AQUA spacecraft have been used to generate operational estimates of SWE and snow depth, complementing estimates generated with other microwave sensors flying on …


Liver Enzymes And Risk Of Ischemic Heart Disease And Type 2 Diabetes Mellitus: A Mendelian Randomization Study, Junxi Liu, Shiu Lun Au Yeung, Gabriel M. Leung, C. Mary Schooling Dec 2016

Liver Enzymes And Risk Of Ischemic Heart Disease And Type 2 Diabetes Mellitus: A Mendelian Randomization Study, Junxi Liu, Shiu Lun Au Yeung, Gabriel M. Leung, C. Mary Schooling

Publications and Research

We used Mendelian randomization to estimate the causal effects of the liver enzymes, alanine aminotransferase (ALT), alkaline phosphatase (ALP) and gamma glutamyltransferase (GGT), on diabetes and cardiovascular disease, using genetic variants predicting these liver enzymes at genome wide significance applied to extensively genotyped case-control studies of diabetes (DIAGRAM) and coronary artery disease (CAD)/myocardial infarction (MI) (CARDIoGRAMplusC4D 1000 Genomes). Genetically higher ALT was associated with higher risk of diabetes, odds ratio (OR) 2.99 per 100% change in concentration (95% confidence interval (CI) 1.62 to 5.52) but ALP OR 0.92 (95% CI 0.71 to 1.19) and GGT OR 0.88 (95% CI 0.75 …


A Mineralized Alga And Acritarch Dominated Microbiota From The Tully Formation (Givetian) Of Pennsylvania, Usa, John A. Chamberlain Jr., Rebecca B. Chamberlain, James O. Brown Dec 2016

A Mineralized Alga And Acritarch Dominated Microbiota From The Tully Formation (Givetian) Of Pennsylvania, Usa, John A. Chamberlain Jr., Rebecca B. Chamberlain, James O. Brown

Publications and Research

Sphaeromorphic algal cysts, most probably of the prasinophyte Tasmanites, and acanthomorphic acritarch vesicles, most probably Solisphaeridium, occur in a single 20 cm thick bed of micritic limestone in the lower part of the Middle Devonian (Givetian) Tully Formation near Lock Haven, Pennsylvania. Specimens are composed of authigenic calcite and pyrite crystals about 5–10 µm in length. Some specimens are completely calcitic; some contain both pyrite and calcite; and many are composed totally of pyrite. The microfossils are about 80 to 150 µm in diameter. Many show signs of originally containing a flexible wall composed of at least two layers. Some …


Burden Of Disease Associated With Lower Levels Of Income Among Us Adults Aged 65 And Older, Erica I. Lubetkin, Haomia Jia Dec 2016

Burden Of Disease Associated With Lower Levels Of Income Among Us Adults Aged 65 And Older, Erica I. Lubetkin, Haomia Jia

Publications and Research

Background: Persons aged 65 years and older represent a heterogeneous group whose prevalence in the USA is expected to markedly increase. Few investigations have examined the total burden of disease attributable to lower levels of income in a single number that accounts for morbidity and mortality.

Methods: We ascertained respondents’ health-related quality of life (HRQOL) scores and mortality status from the 2003 to 2004, 2005 to 2006, 2007 to 2008 and 2009 to 2010 cohorts of the National Health and Nutrition Examination Survey (NHANES) with mortality follow-up through 31 December 2011. A mapping algorithm based on respondents’ age and answers …


Improved Genome-Scale Multitarget Virtual Screening Via A Novel Collaborative Filtering Approach To Cold-Start Problem, Hansaim Lim, Paul Gray, Lei Xie, Aleksandar Poleksic Dec 2016

Improved Genome-Scale Multitarget Virtual Screening Via A Novel Collaborative Filtering Approach To Cold-Start Problem, Hansaim Lim, Paul Gray, Lei Xie, Aleksandar Poleksic

Publications and Research

Conventional one-drug-one-gene approach has been of limited success in modern drug discovery. Polypharmacology, which focuses on searching for multi-targeted drugs to perturb disease-causing networks instead of designing selective ligands to target individual proteins, has emerged as a new drug discovery paradigm. Although many methods for single-target virtual screening have been developed to improve the efficiency of drug discovery, few of these algorithms are designed for polypharmacology. Here, we present a novel theoretical framework and a corresponding algorithm for genome-scale multitarget virtual screening based on the one-class collaborative filtering technique. Our method overcomes the sparseness of the protein-chemical interaction data by …


Siddhartha Mukherjee. The Gene. An Intimate History. New York: Scribner, 2016. 593 Pp. $32.00 Cloth (Isbn 978-1-4767-3350-0), Aldemaro Romero Jr. Dec 2016

Siddhartha Mukherjee. The Gene. An Intimate History. New York: Scribner, 2016. 593 Pp. $32.00 Cloth (Isbn 978-1-4767-3350-0), Aldemaro Romero Jr.

Publications and Research

Heredity has always been, in one form or another, at the center of biological

research. There is little doubt that the first scientific experimentation took place

about fifteen thousand years ago, when humans started breeding plants and

animals in order to domesticate them. Today the science of genetics seems to

advance at such a pace that even the experts have trouble keeping up with all the

developments. Now we are witnessing the expansion of our understanding of this

realm of science to levels unimaginable just a few decades ago.


Higher Ed Sees Decline In Language Studies., Aldemaro Romero Jr. Dec 2016

Higher Ed Sees Decline In Language Studies., Aldemaro Romero Jr.

Publications and Research

Despite much talk about the importance of globalization,

the very places where most people in

the U.S. learn foreign languages – colleges and universities

– are offering fewer and fewer courses in

them. In a report published last year by the Modern

Languages Association (MLA), statistics show that

for the first time since 1995 we are seeing a drop

in enrollment in courses in all major European languages,

including Spanish. And the drop is significant:

6.7 percent overall since 2009 after increasing

steadily since 1995.

Spanish, the most studied language in colleges

and universities (more than all other languages

combined), …


The History Of Algorithmic Complexity, Audrey A. Nasar Dec 2016

The History Of Algorithmic Complexity, Audrey A. Nasar

Publications and Research

This paper provides a historical account of the development of algorithmic complexity in a form that is suitable to instructors of mathematics at the high school or undergraduate level. The study of algorithmic complexity, despite being deeply rooted in mathematics, is usually restricted to the computer science curriculum. By providing a historical account of algorithmic complexity through a mathematical lens, this paper aims to equip mathematics educators with the necessary background and framework for incorporating the analysis of algorithmic complexity into mathematics courses as early on as algebra or pre-calculus.


The Science Teaching Fellows Program: A Model For Online Faculty Development Of Early Career Scientists Interested In Teaching, Loretta Branacaccio-Taras, Kelly A. Gull, Claudia Ratti Dec 2016

The Science Teaching Fellows Program: A Model For Online Faculty Development Of Early Career Scientists Interested In Teaching, Loretta Branacaccio-Taras, Kelly A. Gull, Claudia Ratti

Publications and Research

The American Society for Microbiology (ASM) has a history of providing a wide range of faculty development opportunities. Recently, ASM developed the Science Teaching Fellows Program (STF) for early career biologists and postdoctoral students to explore student-centered teaching and develop the skills needed to succeed in positions that have a significant teaching component. Participants were selected to STF through a competitive application process. The STF program consisted of a series of six webinars. In preparation for each webinar, participants completed a pre-webinar assignment. After each webinar, fellows practiced what they learned by completing a post-webinar assignment. In a survey used …


Flipping The Classroom In Business And Education One-Shot Sessions: A Research Study, Madeline Cohen, Jennifer Poggiali, Alison Lehner-Quam, Robin Wright, Rebecca K. West Dec 2016

Flipping The Classroom In Business And Education One-Shot Sessions: A Research Study, Madeline Cohen, Jennifer Poggiali, Alison Lehner-Quam, Robin Wright, Rebecca K. West

Publications and Research

In response to the challenge of maximising the effectiveness of one-shot information literacy (IL) sessions, library faculty at Lehman College experimented with the flipped classroom model. This research paper reports the results of a multi-semester quantitative study of the flipped classroom in business management and education one-shot sessions. Researchers explored two research questions: Do students in a flipped session demonstrate greater knowledge before their session than students in a control session? and Do flipped and control students demonstrate significant, positive improvement in knowledge after their session? The researchers used pre- and post-tests to evaluate two crucial aspects of the flipped …


The Future Of Web Citation Practices, Robin Camille Davis Dec 2016

The Future Of Web Citation Practices, Robin Camille Davis

Publications and Research

Citing webpages has been a common practice in scholarly publications for nearly two decades as the Web evolved into a major information source. But over the years, more and more bibliographies have suffered from “reference rot”: cited URLs are broken links or point to a page that no longer contains the content the author originally cited. In this column, I look at several studies showing how reference rot has affected different academic disciplines. I also examine citation styles’ approach to citing web sources. I then turn to emerging web citation practices: Perma, a “freemium” web archiving service specifically for citation; …


The Power Of Associative Learning And The Ontogeny Of Optimal Behaviour, Magnus Enquist, Johan Lind, Stefano Ghirlanda Nov 2016

The Power Of Associative Learning And The Ontogeny Of Optimal Behaviour, Magnus Enquist, Johan Lind, Stefano Ghirlanda

Publications and Research

Behaving efficiently (optimally or near-optimally) is central to animals’ adaptation to their environment. Much evolutionary biology assumes, implicitly or explicitly, that optimal behavioural strategies are genetically inherited, yet the behaviour of many animals depends crucially on learning. The question of how learning contributes to optimal behaviour is largely open. Here we propose an associative learning model that can learn optimal behaviour in a wide variety of ecologically relevant circumstances. The model learns through chaining, a term introduced by Skinner to indicate learning of behaviour sequences by linking together shorter sequences or single behaviours. Our model formalizes the concept of conditioned …


Properties Of The Schrödinger Theory Of Electrons In Electromagnetic Fields, Viraht Sahni, Xiao-Yin Pan Nov 2016

Properties Of The Schrödinger Theory Of Electrons In Electromagnetic Fields, Viraht Sahni, Xiao-Yin Pan

Publications and Research

The Schrödinger theory of electrons in an external electromagnetic field can be described from the perspective of the individual electron via the ‘Quantal Newtonian’ laws (or differential virial theorems). These laws are in terms of ‘classical’ fields whose sources are quantal expectations of Hermitian operators taken with respect to the wave function. The laws reveal the following physics: (a) In addition to the external field, each electron experiences an internal field whose components are representative of a specific property of the system such as the correlations due to the Pauli exclusion principle and Coulomb repulsion, the electron density, kinetic effects, …


Triode For Magnetic Flux Quanta, V.K. Vlasko-Vlasov, F. Caluto, Timothy Benseman, D. Rosenmann, W.K. Kwok Nov 2016

Triode For Magnetic Flux Quanta, V.K. Vlasko-Vlasov, F. Caluto, Timothy Benseman, D. Rosenmann, W.K. Kwok

Publications and Research

In an electronic triode, the electron current emanating from the cathode is regulated by the electric potential on a grid between the cathode and the anode. Here we demonstrate a triode for single quantum magnetic field carriers, where the flow of individual magnetic vortices in a superconducting film is regulated by the magnetic potential of striae of soft magnetic strips deposited on the film surface. By rotating an applied in-plane field, the magnetic strip potential can be varied due to changes in the magnetic charges at the strip edges, allowing accelerated or retarded motion of magnetic vortices inside the superconductor. …


Ocean–Atmosphere Interactions Modulate Irrigation’S Climate Impacts, Nir Y. Krakauer, Michael J. Puma, Benjamin I. Cook, Pierre Gentine, Larisa Nazarenko Nov 2016

Ocean–Atmosphere Interactions Modulate Irrigation’S Climate Impacts, Nir Y. Krakauer, Michael J. Puma, Benjamin I. Cook, Pierre Gentine, Larisa Nazarenko

Publications and Research

Numerous studies have focused on the local and regional climate effects of irrigated agriculture and other land cover and land use change (LCLUC) phenomena, but there are few studies on the role of ocean– atmosphere interaction in modulating irrigation climate impacts. Here, we compare simulations with and without interactive sea surface temperatures of the equilibrium effect on climate of contemporary (year 2000) irrigation geographic extent and intensity.We find that ocean–atmosphere interaction does impact the magnitude of globalmean and spatially varying climate impacts, greatly increasing their global reach. Local climate effects in the irrigated regions remain broadly similar, while non-local effects, …


Research Update: The Mechanocaloric Potential Of Spin Crossover Compounds, Karl G. Sandeman Nov 2016

Research Update: The Mechanocaloric Potential Of Spin Crossover Compounds, Karl G. Sandeman

Publications and Research

We present a first evaluation of the potential for spin crossover (SCO) compounds to be considered as a new class of giant mechanocaloric effect materials. From literature data on the variation of the spin crossover temperature with pressure, we estimate the maximum available adiabatic temperature change for several compounds and the relatively low pressures that may be required to observe these effects.


Record Of Massive Upwellings From The Pacific Large Low Shear Velocity Province, Pilar Madrigal, Esteban Gazel, Kennet E. Flores, Michael Bizimis, Brian Jicha Nov 2016

Record Of Massive Upwellings From The Pacific Large Low Shear Velocity Province, Pilar Madrigal, Esteban Gazel, Kennet E. Flores, Michael Bizimis, Brian Jicha

Publications and Research

Global tomography and numerical models suggest that mantle plume occurrences are closely linked to the margins of large low-shear velocity provinces (LLSVPs)1–4. In these marginal zones the ascent of material from the core-mantle boundary connects deep mantle dynamics with surface processes through mantle plume activity, forming large igneous provinces (LIPs) and some of the modern hotspot volcanoes5,6. Petrological7 and geodynamic8 evidence suggest a link between the formation of oceanic plateaus and the interactions of mantle plumes and mid-ocean ridges (MORs). Even though the causality relationship between both processes is still unclear (either rifting is initiated by plume impact or it …


Generalized Least-Powers Regressions I: Bivariate Regressions, Nataniel Greene Nov 2016

Generalized Least-Powers Regressions I: Bivariate Regressions, Nataniel Greene

Publications and Research

The bivariate theory of generalized least-squares is extended here to least-powers. The bivariate generalized least-powers problem of order p seeks a line which minimizes the average generalized mean of the absolute pth power deviations between the data and the line. Least-squares regressions utilize second order moments of the data to construct the regression line whereas least-powers regressions use moments of order p to construct the line. The focus is on even values of p, since this case admits analytic solution methods for the regression coefficients. A numerical example shows generalized least-powers methods performing comparably to generalized least-squares methods, …


Culturally Responsive Teaching: Implications For Educational Justice, Magnus O. Bassey Nov 2016

Culturally Responsive Teaching: Implications For Educational Justice, Magnus O. Bassey

Publications and Research

Educational justice is a major global challenge. In most underdeveloped countries, many students do not have access to education and in most advanced democracies, school attainment and success are still, to a large extent, dependent on a student’s social background. However, it has often been argued that social justice is an essential part of teachers’ work in a democracy. This article raises an important overriding question: how can we realize the goal of educational justice in the field of teaching? In this essay, I examine culturally responsive teaching as an educational practice and conclude that it is possible to realize …


Investigation Of Electric Field–Induced Structural Changes At Fe-Doped Srtio3 Anode Interfaces By Second Harmonic Generation, David Ascienzo, Haochen Yuan, Steven Greenbaum, Thorsten J. Bayer, Russell A. Maier, Jian-Jun Wang, Clive A. Randall, Elizabeth C. Dickey, Haibin Zhao, Yuhang Ren Oct 2016

Investigation Of Electric Field–Induced Structural Changes At Fe-Doped Srtio3 Anode Interfaces By Second Harmonic Generation, David Ascienzo, Haochen Yuan, Steven Greenbaum, Thorsten J. Bayer, Russell A. Maier, Jian-Jun Wang, Clive A. Randall, Elizabeth C. Dickey, Haibin Zhao, Yuhang Ren

Publications and Research

We report on the detection of electric field–induced second harmonic generation (EFISHG) from the anode interfaces of reduced and oxidized Fe-doped SrTiO3 (Fe:STO) single crystals. For the reduced crystal, we observe steady enhancements of the susceptibility components as the imposed dc-voltage increases. The enhancements are attributed to a field-stabilized electrostriction, leading to Fe:Ti-O bond stretching and bending in Fe:Ti-O6 octahedra. For the oxidized crystal, no obvious structural changes are observed below 16 kV/cm. Above 16 kV/cm, a sharp enhancement of the susceptibilities occurs due to local electrostrictive deformations in response to oxygen vacancy migrations away from the anode. Differences between …