Transverse fields to tune an Isingnematic quantum phase transition [Transverse fields to tune an Isingnematic quantum critical transition]
Abstract
Here, the paradigmatic example of a continuous quantum phase transition is the transverse field Ising ferromagnet. In contrast to classical critical systems, whose properties depend only on symmetry and the dimension of space, the nature of a quantum phase transition also depends on the dynamics. In the transverse field Ising model, the order parameter is not conserved, and increasing the transverse field enhances quantum fluctuations until they become strong enough to restore the symmetry of the ground state. Ising pseudospins can represent the order parameter of any system with a twofold degenerate brokensymmetry phase, including electronic nematic order associated with spontaneous pointgroup symmetry breaking. Here, we show for the representative example of orbitalnematic ordering of a nonKramers doublet that an orthogonal strain or a perpendicular magnetic field plays the role of the transverse field, thereby providing a practical route for tuning appropriate materials to a quantum critical point. While the transverse fields are conjugate to seemingly unrelated order parameters, their nontrivial commutation relations with the nematic order parameter, which can be represented by a Berryphase term in an effective field theory, intrinsically intertwine the different order parameters.
 Authors:
 Stanford Univ., Stanford, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
 Stanford Univ., Stanford, CA (United States)
 Weizmann Institute of Science, Rehovot (Israel); Univ. of Chicago, Chicago, IL (United States)
 Univ. of Minnesota, Minneapolis, MN (United States)
 SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., Stanford, CA (United States)
 Publication Date:
 Research Org.:
 SLAC National Accelerator Lab., Menlo Park, CA (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1416346
 Alternate Identifier(s):
 OSTI ID: 1411287
 Grant/Contract Number:
 AC0276SF00515; DGE114747; GBMF4414; SC0012336; 1291/12; 2014209
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Proceedings of the National Academy of Sciences of the United States of America
 Additional Journal Information:
 Journal Volume: 114; Journal Issue: 51; Journal ID: ISSN 00278424
 Publisher:
 National Academy of Sciences, Washington, DC (United States)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; quantum phase transitions; electronic nematicity; strongly correlated electrons; condensed matter physics
Citation Formats
Maharaj, Akash V., Rosenberg, Elliott W., Hristov, Alexander T., Berg, Erez, Fernandes, Rafael M., Fisher, Ian R., and Kivelson, Steven A. Transverse fields to tune an Isingnematic quantum phase transition [Transverse fields to tune an Isingnematic quantum critical transition]. United States: N. p., 2017.
Web. doi:10.1073/pnas.1712533114.
Maharaj, Akash V., Rosenberg, Elliott W., Hristov, Alexander T., Berg, Erez, Fernandes, Rafael M., Fisher, Ian R., & Kivelson, Steven A. Transverse fields to tune an Isingnematic quantum phase transition [Transverse fields to tune an Isingnematic quantum critical transition]. United States. doi:10.1073/pnas.1712533114.
Maharaj, Akash V., Rosenberg, Elliott W., Hristov, Alexander T., Berg, Erez, Fernandes, Rafael M., Fisher, Ian R., and Kivelson, Steven A. 2017.
"Transverse fields to tune an Isingnematic quantum phase transition [Transverse fields to tune an Isingnematic quantum critical transition]". United States.
doi:10.1073/pnas.1712533114.
@article{osti_1416346,
title = {Transverse fields to tune an Isingnematic quantum phase transition [Transverse fields to tune an Isingnematic quantum critical transition]},
author = {Maharaj, Akash V. and Rosenberg, Elliott W. and Hristov, Alexander T. and Berg, Erez and Fernandes, Rafael M. and Fisher, Ian R. and Kivelson, Steven A.},
abstractNote = {Here, the paradigmatic example of a continuous quantum phase transition is the transverse field Ising ferromagnet. In contrast to classical critical systems, whose properties depend only on symmetry and the dimension of space, the nature of a quantum phase transition also depends on the dynamics. In the transverse field Ising model, the order parameter is not conserved, and increasing the transverse field enhances quantum fluctuations until they become strong enough to restore the symmetry of the ground state. Ising pseudospins can represent the order parameter of any system with a twofold degenerate brokensymmetry phase, including electronic nematic order associated with spontaneous pointgroup symmetry breaking. Here, we show for the representative example of orbitalnematic ordering of a nonKramers doublet that an orthogonal strain or a perpendicular magnetic field plays the role of the transverse field, thereby providing a practical route for tuning appropriate materials to a quantum critical point. While the transverse fields are conjugate to seemingly unrelated order parameters, their nontrivial commutation relations with the nematic order parameter, which can be represented by a Berryphase term in an effective field theory, intrinsically intertwine the different order parameters.},
doi = {10.1073/pnas.1712533114},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
number = 51,
volume = 114,
place = {United States},
year = 2017,
month =
}

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