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Full-Text Articles in Physics
Directly Photoexcited Dirac And Weyl Fermions In Zrsis And Nbas, Christopher P. Weber, Leslie M. Schoop, Stuart S. P. Parkin, Robert C. Newby, Alex Nateprov, Bettina Lotsch, Bala Murali Krishna Mariserla, J. Matthew Kim, Keshav M. Dani, Hans A. Bechtel, Ernerst Arushanov, Mazhar Ali
Directly Photoexcited Dirac And Weyl Fermions In Zrsis And Nbas, Christopher P. Weber, Leslie M. Schoop, Stuart S. P. Parkin, Robert C. Newby, Alex Nateprov, Bettina Lotsch, Bala Murali Krishna Mariserla, J. Matthew Kim, Keshav M. Dani, Hans A. Bechtel, Ernerst Arushanov, Mazhar Ali
Physics
We report ultrafast optical measurements of the Dirac line-node semimetal ZrSiS and the Weyl semimetal NbAs, using mid-infrared pump photons from 86 meV to 500 meV to directly excite Dirac and Weyl fermions within the linearly dispersing bands. In NbAs, the photoexcited Weyl fermions initially form a non-thermal distribution, signified by a brief spike in the differential reflectivity whose sign is controlled by the relative energy of the pump and probe photons. In ZrSiS, electron-electron scattering rapidly thermalizes the electrons, and the spike is not observed. Subsequently, hot carriers in both materials cool within a few picoseconds. This cooling, as …
Using Coherent Phonons For Ultrafast Control Of The Dirac Node Of Srmnsb2, Christopher P. Weber, Madison G. Masten, Thomas C. Ogloza, Bryan S. Berggren, Michael K. L. Man, Keshav M. Dani, Jinyu Liu, Zhiqiang Mao, Dennis D. Klug, Adebayo A. Adeleke, Yansun Yao
Using Coherent Phonons For Ultrafast Control Of The Dirac Node Of Srmnsb2, Christopher P. Weber, Madison G. Masten, Thomas C. Ogloza, Bryan S. Berggren, Michael K. L. Man, Keshav M. Dani, Jinyu Liu, Zhiqiang Mao, Dennis D. Klug, Adebayo A. Adeleke, Yansun Yao
Physics
SrMnSb2 is a candidate Dirac semimetal whose electrons near the Y point have the linear dispersion and low mass of a Dirac cone. Here we demonstrate that ultrafast, 800-nm optical pulses can launch coherent phonon oscillations in Sr0.94Mn0.92Sb2, particularly an Ag mode at 4.4 THz. Through first-principles calculations of the electronic and phononic structure of SrMnSb2, we show that high-amplitude oscillations of this mode would displace the atoms in a way that transiently opens and closes a gap at the node of the Dirac cone. The ability to control the …
Structural And Wetting Properties Of Nature's Finest Silks (Order Embioptera), Grace Y. Stokes, Evangelea N. Dicicco, Trevor J. Moore, Vivian C. Cheng, Kira Y. Wheeler, John Soghigian, Richard P. Barber Jr., Janice Edgerly-Rooks
Structural And Wetting Properties Of Nature's Finest Silks (Order Embioptera), Grace Y. Stokes, Evangelea N. Dicicco, Trevor J. Moore, Vivian C. Cheng, Kira Y. Wheeler, John Soghigian, Richard P. Barber Jr., Janice Edgerly-Rooks
Physics
Insects from the order Embioptera (webspinners) spin silk fibres which are less than 200 nm in diameter. In this work, we characterized and compared the diameters of single silk fibres from nine species—Antipaluria urichi, Pararhagadochir trinitatis, Saussurembia calypso, Diradius vandykei, Aposthonia ceylonica, Haploembia solieri, H. tarsalis, Oligotoma nigra and O. saundersii. Silk from seven of these species have not been previously quantified. Our studies cover five of the 10 named taxonomic families and represent about one third of the known taxonomic family-level diversity in the order Embioptera. Naturally spun silk varied …
Energy Loss Due To Defect Formation From 206Pb Recoils In Supercdms Germanium Detectors, R. Agnese, T. Aralis, T. Aramaki, I. J. Arnquist, E. Azadbakht, W. Baker, S. Banik, D. Barker, D. A. Bauer, T. Binder, M. A. Bowles, P. L. Brink, R. Bunker, B. Cabrera, R. Calkins, D. G. Cerdeno, Y.-Y. Chang, J. Cooley, B. Cornell, P. Cushman, P. C. F. Di Stefano, T. Doughty, E. Fascione, E. Figueroa-Feliciano, C. W. Fink, M. Fritts, G. Gerbier, R. Germond, M. Ghaith, S. R. Golwala, H. R. Harris, Z. Hong, E. W. Hoppe, L. Hsu, M. E. Huber, V. Iyer, D. Jardin, C. Jena, M. H. Kelsey, A. Kennedy, A. Kubik, N. A. Kurinsky, R. E. Lawrence, B. Loer, E. Lopez Asamar, P. Lukens, D. Macdonell, R. Mahapatra, V. Mandic, N. Mast, E. H. Miller, N. Mirabolfathi, B. Mohanty, J. D. Morales Mendoza, J. Nelson, J. L. Orrell, S. M. Oser, W. A. Page, R. Partridge, M. Pepin, F. Ponce, S. Poudel, M. Pyle, H. Qui, W. Rau, A. Reisetter, T. Ren, T. Reynolds, A. Roberts, A. E. Robinson, H. E. Rogers, T. Saab, B. Sadoulet, J. Sander, A. Scarff, R. W. Schnee, S. Scorza, K. Senapati, B. Serfass, D. Speller, M. Stein, J. Street, H. A. Tanaka, D. Toback, R. Underwood, A. N. Villano, B. Von Krosigk, S. L. Watkins, J. S. Wilson, M. J. Wilson, J. Winchell, D. H. Wright, S. Yellin, Betty A. Young, X. Zhang, X. Xhao
Energy Loss Due To Defect Formation From 206Pb Recoils In Supercdms Germanium Detectors, R. Agnese, T. Aralis, T. Aramaki, I. J. Arnquist, E. Azadbakht, W. Baker, S. Banik, D. Barker, D. A. Bauer, T. Binder, M. A. Bowles, P. L. Brink, R. Bunker, B. Cabrera, R. Calkins, D. G. Cerdeno, Y.-Y. Chang, J. Cooley, B. Cornell, P. Cushman, P. C. F. Di Stefano, T. Doughty, E. Fascione, E. Figueroa-Feliciano, C. W. Fink, M. Fritts, G. Gerbier, R. Germond, M. Ghaith, S. R. Golwala, H. R. Harris, Z. Hong, E. W. Hoppe, L. Hsu, M. E. Huber, V. Iyer, D. Jardin, C. Jena, M. H. Kelsey, A. Kennedy, A. Kubik, N. A. Kurinsky, R. E. Lawrence, B. Loer, E. Lopez Asamar, P. Lukens, D. Macdonell, R. Mahapatra, V. Mandic, N. Mast, E. H. Miller, N. Mirabolfathi, B. Mohanty, J. D. Morales Mendoza, J. Nelson, J. L. Orrell, S. M. Oser, W. A. Page, R. Partridge, M. Pepin, F. Ponce, S. Poudel, M. Pyle, H. Qui, W. Rau, A. Reisetter, T. Ren, T. Reynolds, A. Roberts, A. E. Robinson, H. E. Rogers, T. Saab, B. Sadoulet, J. Sander, A. Scarff, R. W. Schnee, S. Scorza, K. Senapati, B. Serfass, D. Speller, M. Stein, J. Street, H. A. Tanaka, D. Toback, R. Underwood, A. N. Villano, B. Von Krosigk, S. L. Watkins, J. S. Wilson, M. J. Wilson, J. Winchell, D. H. Wright, S. Yellin, Betty A. Young, X. Zhang, X. Xhao
Physics
The Super Cryogenic Dark Matter Search experiment (SuperCDMS) at the Soudan Underground Laboratory studied energy loss associated with Frenkel defect formation in germanium crystals at mK temperatures using in situ 210Pb sources. We examine the spectrum of 206Pb nuclear recoils near its expected 103 keV endpoint energy and determine an energy loss of (6.08±0.18) %, which we attribute to defect formation. From this result and using TRIM simulations, we extract the first experimentally determined average displacement threshold energy of (19.7+0.6−0.5) eV for germanium. This has implications for the analysis thresholds of future germanium-based dark matter …
First Dark Matter Constraints From A Supercdms Single-Charge Sensitive Detector, R. Agnese, T. Aralis, T. Aramaki, I. J. Arnquist, E. Azadbakht, W. Baker, S. Banik, D. Barker, S. Banik, D. Barker, D. A. Bauer, T. Binder, M. A. Bowles, P. L. Brink, R. Bunker, Blas Cabrera, R. Calkins, C. Cartaro, D. G. Cerdeño, Y. Y. Chang, J. Cooley, B. Cornell, P. Cushman, P. C. F. Di Stefano, T. Doughty, E. Fascione, E. Figueroa-Feliciano, C. Fink, M. Fritts, G. Gerbier, R. Germond, M. Ghaith, S. R. Golwala, H. R. Harris, Z. Hong, E. W. Hoppe, L. Hsu, M. E. Huber, V. Iyers, D. Jardin, C. Jena, M. H. Kelsey, A. Kennedy, A. Kubik, N. A. Kurinsky, R. E. Lawrence, J. V. Leyva, B. Loer, E. Lopez Asamar, P. Lukens, D. Macdonell, R. Mahapatra, V. Mandic, N. Mast, E. H. Miller, N. Mirabolfathi, B. Mohanty, J. D. Morales Mendoza, J. Nelson, J. L. Orrell, S. M. Oser, W. A. Page, R. Partridge, M. Pepin, A. Phipps, F. Ponce, S. Poudel, M. Pyle, H. Qui, W. Rau, A. Reisetter, T. Reynolds, A. Roberts, A. E. Robinson, H. E. Rogers, R. K. Romani, T. Saab, B. Sadoulet, J. Sander, A. Scarff, R. W. Schnee, S. Scorza, K. Senapati, B. Serfass, J. So, D. Speller, C. Stanford, M. Stein, J. Street, H. A. Tanaka, D. Toback, R. Underwood, A. N. Villano, B. Von Krosigk, S. L. Watkins, J. S. Wilson, M. J. Wilson, J. Winchell, D. H. Wright, S. Yellin, Betty A. Young, X. Zhang, X. Zhao
First Dark Matter Constraints From A Supercdms Single-Charge Sensitive Detector, R. Agnese, T. Aralis, T. Aramaki, I. J. Arnquist, E. Azadbakht, W. Baker, S. Banik, D. Barker, S. Banik, D. Barker, D. A. Bauer, T. Binder, M. A. Bowles, P. L. Brink, R. Bunker, Blas Cabrera, R. Calkins, C. Cartaro, D. G. Cerdeño, Y. Y. Chang, J. Cooley, B. Cornell, P. Cushman, P. C. F. Di Stefano, T. Doughty, E. Fascione, E. Figueroa-Feliciano, C. Fink, M. Fritts, G. Gerbier, R. Germond, M. Ghaith, S. R. Golwala, H. R. Harris, Z. Hong, E. W. Hoppe, L. Hsu, M. E. Huber, V. Iyers, D. Jardin, C. Jena, M. H. Kelsey, A. Kennedy, A. Kubik, N. A. Kurinsky, R. E. Lawrence, J. V. Leyva, B. Loer, E. Lopez Asamar, P. Lukens, D. Macdonell, R. Mahapatra, V. Mandic, N. Mast, E. H. Miller, N. Mirabolfathi, B. Mohanty, J. D. Morales Mendoza, J. Nelson, J. L. Orrell, S. M. Oser, W. A. Page, R. Partridge, M. Pepin, A. Phipps, F. Ponce, S. Poudel, M. Pyle, H. Qui, W. Rau, A. Reisetter, T. Reynolds, A. Roberts, A. E. Robinson, H. E. Rogers, R. K. Romani, T. Saab, B. Sadoulet, J. Sander, A. Scarff, R. W. Schnee, S. Scorza, K. Senapati, B. Serfass, J. So, D. Speller, C. Stanford, M. Stein, J. Street, H. A. Tanaka, D. Toback, R. Underwood, A. N. Villano, B. Von Krosigk, S. L. Watkins, J. S. Wilson, M. J. Wilson, J. Winchell, D. H. Wright, S. Yellin, Betty A. Young, X. Zhang, X. Zhao
Physics
We present the first limits on inelastic electron-scattering dark matter and dark photon absorption using a prototype SuperCDMS detector having a charge resolution of 0.1 electron-hole pairs (CDMS HVeV, a 0.93 gram CDMS HV device). These electron-recoil limits significantly improve experimental constraints on dark matter particles with masses as low as 1 MeV/c2. We demonstrate a sensitivity to dark photons competitive with other leading approaches but using substantially less exposure (0.49 gram days). These results demonstrate the scientific potential of phonon-mediated semiconductor detectors that are sensitive to single electronic excitations.
Time-Dependent Efficiency Measurements Of Polymer Solar Cells With Dye Additives: Unexpected Initial Increase Of Efficiency, Kyle J. Bandaccari, Grace E. Chesmore, Mitchel Bugaj, Parisa Tajalli-Tehrani Valverde, Richard P. Barber Jr., Brian J. Mcnelis
Time-Dependent Efficiency Measurements Of Polymer Solar Cells With Dye Additives: Unexpected Initial Increase Of Efficiency, Kyle J. Bandaccari, Grace E. Chesmore, Mitchel Bugaj, Parisa Tajalli-Tehrani Valverde, Richard P. Barber Jr., Brian J. Mcnelis
Physics
We report the effects of the addition of two azo-dye additives on the time-dependent efficiency of polymer solar cells. Although the maximum efficiencies of devices containing different amounts of dye do not vary greatly over the selected concentration range, the time dependence results reveal a surprising initial increase in efficiency in some samples. We observe this effect to be correlated with a leakage current, although a specific mechanism is not yet identified. We also present the measured lifetimes of these solar cells, and find that variations in dye concentrations produce a small effect at most. Characterization of the bulk heterojunction …
Results From The Super Cryogenic Dark Matter Search (Supercdms) Experiment At Soudan, R. Agnese, T. Aramaki, I. J. Arnquist, W. Baker, D. Balakishiyeva, S. Banik, D. Barker, R. Basu Thakur, D. A. Bauer, T. Binder, M. A. Bowles, P. L. Brink, R. Bunker, Blas Cabrera, D. O. Caldwell, R. Calkins, C. Cartaro, D. G. Cerdeño, Y. Chang, Y. Chen, J. Cooley, B. Cornell, P. Cushman, M. Daal, P. C. F. Di Stefano, T. Doughty, E. Fascione, E. Figueroa-Feliciano, M. Fritts, G. Gerbier, R. Germond, M. Ghaith, G. L. Godfrey, S. R. Golwala, J. Hall, H. R. Harris, Z. Hong, E. W. Hoppe, L. Hsu, M. E. Huber, V. Iyer, D. Jardin, A. Jastram, C. Jena, M. H. Kelsey, A. Kennedy, A. Kubik, N. A. Kurinsky, B. Loer, E. Lopez Asamar, P. Lukens, D. Macdonell, R. Mahapatra, V. Mandic, N. Mast, E. H. Miller, N. Page, W. A. Page, R. Partridge, M. Penalver Martinez, M. Pepin, A. Phipps, S. Poudel, M. Pyle, H. Qiu, W. Rau, P. Redl, A. Reisetter, T. Reynolds, A. Roberts, A. E. Robinson, H. E. Rogers, T. Saab, B. Sadoulet, J. Sander, K. Schneck, R. W. Schnee, S. Scorza, K. Senapati, B. Serfass, D. Speller, M. Stein, J. Street, H. A. Tanaka, D. Toback, R. Underwood, A. N. Villano, B. Von Krosigk, B. Welliver, J. S. Wilson, M. J. Wilson, D. H. Wright, S. Yellin, J. J. Yen, Betty A. Young, X. Zhang, X Zhao
Results From The Super Cryogenic Dark Matter Search (Supercdms) Experiment At Soudan, R. Agnese, T. Aramaki, I. J. Arnquist, W. Baker, D. Balakishiyeva, S. Banik, D. Barker, R. Basu Thakur, D. A. Bauer, T. Binder, M. A. Bowles, P. L. Brink, R. Bunker, Blas Cabrera, D. O. Caldwell, R. Calkins, C. Cartaro, D. G. Cerdeño, Y. Chang, Y. Chen, J. Cooley, B. Cornell, P. Cushman, M. Daal, P. C. F. Di Stefano, T. Doughty, E. Fascione, E. Figueroa-Feliciano, M. Fritts, G. Gerbier, R. Germond, M. Ghaith, G. L. Godfrey, S. R. Golwala, J. Hall, H. R. Harris, Z. Hong, E. W. Hoppe, L. Hsu, M. E. Huber, V. Iyer, D. Jardin, A. Jastram, C. Jena, M. H. Kelsey, A. Kennedy, A. Kubik, N. A. Kurinsky, B. Loer, E. Lopez Asamar, P. Lukens, D. Macdonell, R. Mahapatra, V. Mandic, N. Mast, E. H. Miller, N. Page, W. A. Page, R. Partridge, M. Penalver Martinez, M. Pepin, A. Phipps, S. Poudel, M. Pyle, H. Qiu, W. Rau, P. Redl, A. Reisetter, T. Reynolds, A. Roberts, A. E. Robinson, H. E. Rogers, T. Saab, B. Sadoulet, J. Sander, K. Schneck, R. W. Schnee, S. Scorza, K. Senapati, B. Serfass, D. Speller, M. Stein, J. Street, H. A. Tanaka, D. Toback, R. Underwood, A. N. Villano, B. Von Krosigk, B. Welliver, J. S. Wilson, M. J. Wilson, D. H. Wright, S. Yellin, J. J. Yen, Betty A. Young, X. Zhang, X Zhao
Physics
We report the result of a blinded search for Weakly Interacting Massive Particles (WIMPs) using the majority of the SuperCDMS Soudan dataset. With an exposure of 1690 kg days, a single candidate event is observed, consistent with expected backgrounds. This analysis (combined with previous Ge results) sets an upper limit on the spin-independent WIMP--nucleon cross section of 1.4×10−44 (1.0×10−44) cm2 at 46 GeV/c2. These results set the strongest limits for WIMP--germanium-nucleus interactions for masses >12 GeV/c2.
Thermal Detection Of Single E-H Pairs In A Biased Silicon Crystal Detector, R. K. Romani, P. L. Brink, Blas Cabrera, M. Cherry, T. Howarth, N. Kurinsky, R. A. Moffatt, R. Partiridge, F. Ponce, M. Pyle, A. Tomada, S. Yellin, J. J. Yen, Betty A. Young
Thermal Detection Of Single E-H Pairs In A Biased Silicon Crystal Detector, R. K. Romani, P. L. Brink, Blas Cabrera, M. Cherry, T. Howarth, N. Kurinsky, R. A. Moffatt, R. Partiridge, F. Ponce, M. Pyle, A. Tomada, S. Yellin, J. J. Yen, Betty A. Young
Physics
We demonstrate that individual electron-hole pairs are resolved in a 1 cm2 by 4 mm thick silicon crystal (0.93 g) operated at ∼35 mK. One side of the detector is patterned with two quasiparticle-trap-assisted electro-thermal-feedback transition edge sensor arrays held near ground potential. The other side contains a bias grid with 20% coverage. Bias potentials up to ±160 V were used in the work reported here. A fiber optic provides 650 nm (1.9 eV) photons that each produce an electron-hole (e– h+) pair in the crystal near the grid. The energy of the drifting charges is …
Low-Mass Dark Matter Search With Cdmslite, R. Agnese, A. J. Anderson, T. Aralis, T. Aramaki, I. J. Arnquist, W. Baker, D. Balakishiyeva, D. Barker, R. Basu Thakur, D. A. Bauer, T. Binder, M. A. Bowles, P. L. Brink, R. Bunker, Blas Cabrera, D. O. Caldwell, R. Calkins, C. Cartaro, D. G. Cerdeño, Y. Chang, H. Chagani, Y. Chen, J. Cooley, B. Cornell, P. Cushman, M. Daal, P.C. F. Di Stefano, T. Doughty, L. Esteban, E. Fascione, E. Figueroa-Feliciano, M. Fritts, G. Gerbier, M. Ghaith, G. L. Godfrey, S. R. Golwala, J. Hall, H. R. Harris, Z. Hong, E. W. Hoppe, L. Hsu, M. E. Huber, V. Iyer, D. Jardin, A. Jastram, C. Jena, M. H. Kelsey, A. Kennedy, A. Kubik, N. A. Kurinsky, A. Leder, B. Loer, E. Lopez Asamar, P. Lukens, D. Macdonell, R. Mahapatra, V. Mandic, N. Mast, E. H. Miller, N. Mirabolfathi, R. A. Moffatt, B. Mohanty, J. D. Morales Mendoza, J. Nelson, J. L. Orrell, S. M. Oser, K. Page, W. A. Page, R. Patridge, M. Pepin, M. Peñalver Martinez, A. Phipps, S. Poudel, M. Pyle, H. Qiu, W. Saab, B. Sadoulet, J. Sander, K. Schneck, R. W. Schnee, S. Scorza, K. Senapati, B. Serfass, D. Speller, M. Stein, J. Street, H. A. Tanaka, D. Toback, R. Underwood, A. N. Villano, B. Von Krosigk, B. Welliver, J. S. Wilson, M. J. Wilson, D. H. Wright, S. Yellin, J. J. Yen, Betty A. Young, X. Zhang, X. Zhao
Low-Mass Dark Matter Search With Cdmslite, R. Agnese, A. J. Anderson, T. Aralis, T. Aramaki, I. J. Arnquist, W. Baker, D. Balakishiyeva, D. Barker, R. Basu Thakur, D. A. Bauer, T. Binder, M. A. Bowles, P. L. Brink, R. Bunker, Blas Cabrera, D. O. Caldwell, R. Calkins, C. Cartaro, D. G. Cerdeño, Y. Chang, H. Chagani, Y. Chen, J. Cooley, B. Cornell, P. Cushman, M. Daal, P.C. F. Di Stefano, T. Doughty, L. Esteban, E. Fascione, E. Figueroa-Feliciano, M. Fritts, G. Gerbier, M. Ghaith, G. L. Godfrey, S. R. Golwala, J. Hall, H. R. Harris, Z. Hong, E. W. Hoppe, L. Hsu, M. E. Huber, V. Iyer, D. Jardin, A. Jastram, C. Jena, M. H. Kelsey, A. Kennedy, A. Kubik, N. A. Kurinsky, A. Leder, B. Loer, E. Lopez Asamar, P. Lukens, D. Macdonell, R. Mahapatra, V. Mandic, N. Mast, E. H. Miller, N. Mirabolfathi, R. A. Moffatt, B. Mohanty, J. D. Morales Mendoza, J. Nelson, J. L. Orrell, S. M. Oser, K. Page, W. A. Page, R. Patridge, M. Pepin, M. Peñalver Martinez, A. Phipps, S. Poudel, M. Pyle, H. Qiu, W. Saab, B. Sadoulet, J. Sander, K. Schneck, R. W. Schnee, S. Scorza, K. Senapati, B. Serfass, D. Speller, M. Stein, J. Street, H. A. Tanaka, D. Toback, R. Underwood, A. N. Villano, B. Von Krosigk, B. Welliver, J. S. Wilson, M. J. Wilson, D. H. Wright, S. Yellin, J. J. Yen, Betty A. Young, X. Zhang, X. Zhao
Physics
The SuperCDMS experiment is designed to directly detect weakly interacting massive particles (WIMPs) that may constitute the dark matter in our Galaxy. During its operation at the Soudan Underground Laboratory, germanium detectors were run in the CDMSlite mode to gather data sets with sensitivity specifically for WIMPs with masses /c2. In this mode, a higher detector-bias voltage is applied to amplify the phonon signals produced by drifting charges. This paper presents studies of the experimental noise and its effect on the achievable energy threshold, which is demonstrated to be as low as 56 eVee (electron equivalent energy). …