Pumping charge with ac magnetic fluxes and the dynamical breakdown of Onsager symmetry

Abstract

We study the transport properties of setups with one and two mesoscopic rings threaded by ac magnetic fluxes of the form (t) = dc + ac cos( 0 t + δ) and connected to two different particle reservoirs. We analyze the conditions to generate a pumped dc current in the adiabatic regime. We also study the symmetry properties of the induced dc current as a function of the static component of the flux dc with and without a dc bias voltage applied at the reservoirs. We analyze, in particular, the validity of the Onsager-Casimir relations for different configurations of the setups.

Magnetic-field asymmetry of nonlinear thermoelectric and heat transport

“…Thus, in the limit B → 0, A X 11,11 = A X 12,21 = 1 (X = G, L, R, K). Note that even in this B → 0 limit, the symmetry parameters X 11,11 and X 12,21 can have deviations from 1, owing to the nonlinear effects irrelevant to B-asymmetry as discussed below equation (9) in section 2 of the main text.…”

“…A prominent example is the breakdown of the Onsager-Casimir relations that manifest themselves in the differential conductance out of equilibrium [1,2]. The effect is due to asymmetric properties of electron-electron interactions under reversal of an external magnetic field and has been extensively studied in the last decade, both theoretically [1][2][3][4][5][6][7][8][9] and experimentally [10][11][12][13][14][15][16][17]. These results are relevant to characterizing nonlinear rectification phenomena in ballistic conductors [18][19][20][21][22][23][24].…”

Dynamics of energy transport and entropy production in ac-driven quantum electron systems

“…or equivalently the scattering matrix, in powers of ω [40,61,62]. By keeping terms up to first order in ω, we get…”

Adiabatic response and quantum thermoelectrics for ac-driven quantum systems

“…[30][31][32][33][34][35] The relation in Eq. (7) implies that there is still an Onsager relation associated with the pumped charge, but it does not relate the pumped charge to itself but rather to the nonconservative force in response to an applied bias.…”