TY - JOUR
T1 - Direct observation of the quantum fluctuation driven amplitude mode in a microcavity polariton condensate
AU - Steger, Mark
AU - Hanai, Ryo
AU - Edelman, Alexander Orson
AU - Littlewood, Peter B.
AU - Snoke, David W.
AU - Beaumariage, Jonathan
AU - Fluegel, Brian
AU - West, Ken
AU - Pfeiffer, Loren N.
AU - Mascarenhas, Angelo
N1 - This paper was authored in part by the National Renewable Energy Laboratory (NREL), operated by Alliance for Sustainable Energy, LLC, for the US Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding was provided by DOE, Office of Science, Basic Energy Sciences (DE-AC36-08GO28308) and by the NREL Laboratory-Directed Research and Development program. Work at Argonne was supported by DOE, Office of Science, Basic Energy Sciences, Materials Science and Engineering under Contract No. DE-AC02-06CH11357. R.H. was supported by a Grand-in-Aid for JSPS fellows (Grant No. 17J01238). The work of sample fabrication at Princeton was funded by the Gordon and Betty Moore Foundation (GBMF-4420) and by the National Science Foundation MRSEC program through the Princeton Center for Complex Materials (DMR-0819860).
PY - 2021/5/14
Y1 - 2021/5/14
N2 - The Higgs amplitude mode is a collective excitation studied and observed in a broad class of matter, including superconductors, charge density waves, antiferromagnets, He3 p-wave superfluid, and ultracold atomic condensates. In all the observations reported thus far, the amplitude mode was excited by perturbing the condensate out of equilibrium. Studying an exciton-polariton condensate, here, we report the observation of this amplitude mode purely driven by intrinsic quantum fluctuations without such perturbations. By using an ultrahigh quality microcavity and a Raman spectrometer to maximally reject photoluminescence (PL) from the condensate, we observe weak but distinct PL at energies below the condensate emission. We identify this as the so-called ghost branches of the amplitude mode arising from quantum depletion of the condensate into this mode. These energies, as well as the overall structure of the PL spectra, are in good agreement with our theoretical analysis.
AB - The Higgs amplitude mode is a collective excitation studied and observed in a broad class of matter, including superconductors, charge density waves, antiferromagnets, He3 p-wave superfluid, and ultracold atomic condensates. In all the observations reported thus far, the amplitude mode was excited by perturbing the condensate out of equilibrium. Studying an exciton-polariton condensate, here, we report the observation of this amplitude mode purely driven by intrinsic quantum fluctuations without such perturbations. By using an ultrahigh quality microcavity and a Raman spectrometer to maximally reject photoluminescence (PL) from the condensate, we observe weak but distinct PL at energies below the condensate emission. We identify this as the so-called ghost branches of the amplitude mode arising from quantum depletion of the condensate into this mode. These energies, as well as the overall structure of the PL spectra, are in good agreement with our theoretical analysis.
KW - Exciton polariton
KW - Extensions of Higgs sector
KW - Luminescence
KW - Quantum phase transitions
UR - http://www.scopus.com/inward/record.url?scp=85106365975&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.103.205125
DO - 10.1103/PhysRevB.103.205125
M3 - Article
AN - SCOPUS:85106365975
SN - 2469-9950
VL - 103
JO - Physical Review B
JF - Physical Review B
IS - 20
M1 - 205125
ER -