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Hattori, Kazumasa*; Ishitobi, Takayuki; Tsunetsugu, Hirokazu*
Physical Review Research (Internet), 6(4), p.L042068_1 - L042068_7, 2024/12
Catumba, G.*; Hiraguchi, Atsuki; Hou, W.-S.*; Jansen, K.*; Kao, Y.-J.*; David Lin, C.-J.*; Ramos, A.*; Sarkar, M.*
Physical Review Research (Internet), 6(4), p.043172_1 - 043172_12, 2024/11
Gauge theories with matter fields in various representations play an important role in different branches of physics. Recently, it was proposed that several aspects of the interesting pseudogap phase of cuprate superconductors near optimal doping may be explained by an emergent SU(2) gauge symmetry. Around the transition with positive hole-doping, one can construct a (2+1)-dimensional SU(2) gauge theory coupled to four adjoint scalar fields which gives rise to a rich phase diagram with a myriad of phases having different broken symmetries. We study the phase diagram of this model on the Euclidean lattice using the Hybrid Monte Carlo algorithm. We find the existence of multiple broken phases as predicted by previous mean field studies. Depending on the quartic couplings, the SU(2) gauge symmetry is broken down either to U(1) or in the perturbative description of the model. We further study the confinement-deconfinement transition in this theory, and find that both the broken phases are deconfining in the range of volumes that we studied. However, there exists a marked difference in the behavior of the Polyakov loop between the two phases.
Shamoto, Shinichi; Yamauchi, Hiroki; Iida, Kazuki*; Ikeuchi, Kazuhiko*; Kaneko, Koji; Chen, Y.-S.*; Yano, Shinichiro*; Hsu, P.-T.*; Lee, M. K.*; Hall, A. E.*; et al.
Physical Review Research (Internet), 6(3), p.033303_1 - 033303_7, 2024/09
The magnetic excitation extends at least from 0.3 to 140 meV. The integrated inelastic scattering intensity leads to a localized magnetic moment of about 5 per Mn site fluctuating at 200 K in the wide energy range, although the long-range ordered magnetic moment is only 2.61
at 4 K. The result suggests that a large part of the magnetic moment does not order in Mn
RhSi.
Sarenac, D.*; Gorbet, G.*; Clark, C. W.*; Cory, D. G.*; Ekinci, H.*; Henderson, M. E.*; Huber, M. G.*; Hussey, D. S.*; Kapahi, C.*; Kienzle, P. A.*; et al.
Physical Review Research (Internet), 6(3), p.L032054_1 - L032054_8, 2024/09
Nakata, Koki; Zou, J.*; Klinovaja, J.*; Loss, D.*
Physical Review Research (Internet), 6(3), p.033207_1 - 033207_11, 2024/08
Tsuchiya, Jun*; Shiga, Motoyuki; Tsuneyuki, Shinji*; Thompson, E. C.*
Physical Review Research (Internet), 6(2), p.023302_1 - 023302_6, 2024/06
We investigate the effect of nuclear quantum effects (NQEs) of hydrogen atoms on the elasticity of ice VII at high pressure and ambient temperature conditions using ab initio path-integral molecular dynamics (PIMD) calculations. We find that the NQEs of hydrogen contributes to the transition of ice VII from a static disordered structure to a dynamically disordered structure at pressures exceeding 40 GPa. This transition is marked by a discontinuous increase of the elastic constants. Comparison of molecular dynamics and PIMD calculations reveal that NQEs increase the elastic constants of ice by about 20% at 70 GPa and 300 K.
Sarenac, D.*; Gorbet, G.*; Kapahi, C.*; Clark, C. W.*; Cory, D. G.*; Ekinci, H.*; Garrad, D. V.*; Henderson, M. E.*; Huber, M. G.*; Hussey, D.*; et al.
Physical Review Research (Internet), 6(2), p.023260_1 - 023260_15, 2024/06
Nagl, J.*; Flavin, D.*; Hayashida, S.*; Povarov, K. Y.*; Yan, M.*; Murai, Naoki; Kawamura, Seiko; Simutis, F.*; Hicken, T. J.*; Luetkens, H.*; et al.
Physical Review Research (Internet), 6(2), p.023267_1 - 023267_18, 2024/06
Rapp, L.*; Matsuoka, Takeshi*; Firestein, K. L.*; Sagae, Daisuke*; Habara, Hideaki*; Mukai, Keiichiro*; Tanaka, Kazuo*; Gamaly, E. G.*; Kodama, Ryosuke*; Seto, Yusuke*; et al.
Physical Review Research (Internet), 6(2), p.023101_1 - 023101_18, 2024/04
It is generally known that irradiating a solid surface with a laser pulse of ultra-relativistic intensity generates a plasma on the surface, which in turn creates an ultrahigh pressure inside. In this study, the crystal structure analysis of high-pressure phases generated inside silicon single-crystals irradiated by this laser was performed using the diffraction system at the Stress and Imaging apparatus of BL22XU, which is a JAEA-BL. The results obtained confirm the existence of high-pressure phases that silicon is said to possess: body-centered, rhombohedral, hexagonal, and tetragonal phases in the interior. We can get the results that the crystal structure of silicon polymorphs of being include body-centered, rhombohedral, hexagonal-diamond, tetragonal exists. In the future, we will accumulate data and apply them to control the internal structure, strength, and functionality of materials.
Yamauchi, Hiroki; Sari, D. P.*; Yasui, Yukio*; Sakakura, Terutoshi*; Kimura, Hiroyuki*; Nakao, Akiko*; Ohara, Takashi; Honda, Takashi*; Kodama, Katsuaki; Igawa, Naoki; et al.
Physical Review Research (Internet), 6(1), p.013144_1 - 013144_9, 2024/02
Kofu, Maiko; Kawamura, Seiko; Murai, Naoki; Ishii, Rieko*; Hirai, Daigoro*; Arima, Hiroshi*; Funakoshi, Kenichi*
Physical Review Research (Internet), 6(1), p.013006_1 - 013006_9, 2024/01
Visuri, A.-M.*; Mohan, J.*; Uchino, Shun; Huang, M.-Z.*; Esslinger, T.*; Giamarchi, T.*
Physical Review Research (Internet), 5(3), p.033095_1 - 033095_11, 2023/08
We study the current-voltage characteristics of a superconducting junction with particle losses at the contacts. We adopt the Keldysh formalism to compute the steady-state current for varying transmission of the contact. In the low transmission regime, the dissipation leads to an enhancement of the current at low bias, a nonmonotonic dependence of current on dissipation, and the emergence of new structures in the current-voltage curves. The effect of dissipation by particle loss is found to be qualitatively different from that of a finite temperature and a finite inelastic scattering rate in the reservoirs.
Nakayama, Katsumasa*; Suzuki, Kei
Physical Review Research (Internet), 5(2), p.L022054_1 - L022054_6, 2023/06
The Casimir effect is a fundamental quantum phenomenon induced by the zero-point energy for a quantum field. It is well-known for relativistic fields with a linear dispersion relation, while its existence or absence for nonrelativistic fields with a quadratic dispersion is an unsettled question. Here, we investigate the Casimir effects for various dispersion relations on the lattice. We find that Casimir effects for dispersions proportional to an even power of momentum are absent in a long distance under some types of boundary conditions, while a remnant of the Casimir effect survives in a short distance. The concepts of such absence and remnants of Casimir effect help us to understand observables in finite-size materials with quantum fields on the lattice, such as thin films, narrow nanoribbons, and short nanowires. In terms of this effect, we also give a reinterpretation of the Casimir effect for massive fields.
Sekino, Yuta*; Tajima, Hiroyuki*; Uchino, Shun
Physical Review Research (Internet), 5(2), p.023058_1 - 023058_12, 2023/04
We investigate the spectrum of spin conductivity for a miscible two-component Bose-Einstein condensate (BEC) that exhibits spin superfluidity. By using the Bogoliubov theory, the regular part being the spin conductivity at finite ac frequency and the spin Drude weight characterizingthe delta-function peak at zero frequency are analytically computed. We demonstrate that the spectrum exhibits a power-law behavior at low frequency, reflecting gapless density and spin modes specific to the binary BEC. At the phase transition points into immiscible and quantum-dropletstates, the change in quasiparticle dispersion relations modifies the power law. In addition, the spin Drude weight becomes finite, indicating zero spin resistivity due to spin superfluidity. Our results also suggest that the Andreev-Bashkin drag density is accessible by measuring the spin conductivity spectrum.
Ishihara, Kota*; Kobayashi, Masayuki*; Imamura, Kumpei*; Konczykowski, M.*; Sakai, Hironori; Opletal, P.; Tokiwa, Yoshifumi; Haga, Yoshinori; Hashimoto, Kenichiro*; Shibauchi, Takasada*
Physical Review Research (Internet), 5(2), p.L022002_1 - L022002_6, 2023/04
Lower superconducting critical fields of UTe
have been determined. Orthorhombic UTe
has magnetic easy axis along the
-axis. We found
perpendicular to
showed anomalous enhancement. By comparing with anisotropy of upper critical fields, effect of magnetic fluctuations on superconductivity is suggested.
Sekino, Yuta*; Tajima, Hiroyuki*; Uchino, Shun
Physical Review Research (Internet), 4(4), p.043014_1 - 043014_16, 2022/10
We show that the optical spin conductivity being a small AC response of a bulk spin current and elusive in condensed matter systems can be measured in ultracold atoms. We demonstrate that this conductivity contains rich information on quantum states by analyzing experimentally achievable systems. The obtained conductivity spectra being absent in the Drude conductivity reflect quasiparticle excitations and non-Fermi liquid properties. Unlike its mass transport counterpart, the spin conductivity serves as a probe applicable to clean atomic gases without disorder and lattice potentials. Our formalism can be generalized to various systems such as spin-orbit coupled and nonequilibrium systems.
Machida, Tadashi*; Nagai, Yuki; Hanaguri, Tetsuo*
Physical Review Research (Internet), 4(3), p.033182_1 - 033182_12, 2022/09
no abstracts in English
Omasa, Yoshinori*; Takagi, Shigeyuki*; Toshima, Kento*; Yokoyama, Kaito*; Endo, Wataru*; Orimo, Shinichi*; Saito, Hiroyuki*; Yamada, Takeshi*; Kawakita, Yukinobu; Ikeda, Kazutaka*; et al.
Physical Review Research (Internet), 4(3), p.033215_1 - 033215_9, 2022/09
Helson, V.*; Zwettler, T.*; Roux, K.*; Konishi, Hideki*; Uchino, Shun; Brantut, J.-P.*
Physical Review Research (Internet), 4(3), p.033199_1 - 033199_10, 2022/09
We study a Fermi gas with strong, tunable interactions dispersively coupled to a high-finesse cavity. Upon probing the system along the cavity axis, we observe a strong optomechanical Kerr nonlinearity originating from the density response of the gas to the intracavity field. Measuring the non-linearity as a function of interaction strength, we extract the zero-frequency density response function of the Fermi gas, and find an increase by a factor of two from the Bardeen-Cooper-Schrieffer to the Bose-Einstein condensate regime. The results are in quantitative agreement with a theory based on operator-product expansion, expressing the density response in terms of universal functions of the interactions, the contact and the internal energy of the gas.
Sheng, Q.*; Kaneko, Tatsuya*; Yamakawa, Kohtaro*; Guguchia, Z.*; Gong, Z.*; Zhao, G.*; Dai, G.*; Jin, C.*; Guo, S.*; Fu, L.*; et al.
Physical Review Research (Internet), 4(3), p.033172_1 - 033172_14, 2022/09