Symmetry Properties of Mixed and Heat Photo-Assisted Noise in the Quantum Hall Regime

Abstract

We investigate the photo-assisted charge-heat mixed noise and the heat noise generated by periodic drives in Quantum Hall states belonging to the Laughlin sequence. Fluctuations of the charge and heat currents are due to weak backscattering induced in a quantum point contact geometry and are evaluated at the lowest order in the tunneling amplitude. Focusing on the cases of a cosine and Lorentzian periodic drive, we show that the different symmetries of the photo-assisted tunneling amplitudes strongly affect the overall profile of these quantities as a function of the AC and DC voltage contributions, which can be tuned independently in experiments.

Suppression of the radiation squeezing in interacting quantum Hall edge channels

“…In the cosine case for a non-zero θ (right panel of Figure ( 3)), it is evident the almost total suppression of the squeezing because the minimum of the quadrature A 2 0 ( A 2 π ) is only slightly below the quantum vacuum (horizontal gray dashed line) while the other stays well above. Concerning Figure 3, the symmetry between the two quadratures for (q → −q), observed in the non-interacting case [31], is still preserved in the interacting one according to the general properties of the photo-assisted amplitudes [64,65]. When we turn our attention to the Lorentzian case, in Figure 4, the situation appears quite different.…”

“…When we turn our attention to the Lorentzian case, in Figure 4, the situation appears quite different. First of all, the mirror symmetry encountered for the cosine drive is absent here [64,65]. Then, the interactions still increase the values of the quadratures' minima but A 2 π , for q = 1, continues to stay well below the quantum vacuum limit.…”

Levitons in helical liquids with Rashba spin-orbit coupling probed by a superconducting contact

“…Coefficients in Eq. ( 19) represent the probability amplitude for electrons to absorb (l > 0) or emit (l < 0) a photon at energy ω and, for this reason, are called photo-assisted coefficient [3,110,111]. By defining the following fermionic annihilation operator…”

Quantum Transport in Mesoscopic Systems

“…In mesoscopic conductors, not only charge, but also heat fluctuations, are significant. This leads to heat and mixed charge-heat correlators, as illustrated by Ronetti et al [ 21 ] for a harmonically driven quantum Hall bar. The system shows quasiparticle excitations of fractional charge (Laughlin states), and it is demonstrated that the mixed noise differs for integer and fractional filling factors.…”