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Topological charge pumping occurs in the adiabatic limit, and the non-adiabatic effect due to finite ramping velocity reduces the pumping efficiency and leads to deviation from quantized charge pumping. In this work, we discuss the relation…

Mesoscale and Nanoscale Physics · Physics 2024-02-09 Fan Yang , Xingyu Li , Hui Zhai

We study the effect of Markovian environmental noise on the dynamics of a two-level quantum system which is steered adiabatically by an external driving field. We express the master equation taking consistently into account all the…

Quantum Physics · Physics 2011-01-10 P. Solinas , M. Möttönen , J. Salmilehto , J. P. Pekola

We study the adiabatic quantum pumping characteristics in the graphene modulated by two oscillating gate potentials out of phase. The angular and energy dependence of the pumped current is presented. The direction of the pumped current can…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Rui Zhu , Huiming Chen

We propose an arbitrary driven spin as the working fluid of a quantum Otto cycle in the presence of internal friction. The role of total allocated time to the adiabatic branches of the cycle, generated by different control field profiles,…

Quantum Physics · Physics 2017-05-17 Selcuk Cakmak , Ferdi Altintas , Ozgur E. Mustecaplioglu

The efficiency of a quantum heat engine is maximum when the unitary strokes are adiabatic. On the other hand, this may not be always possible due to small energy gaps in the system, especially at the critical point where the gap vanishes.…

Quantum Physics · Physics 2024-07-08 Revathy B. S , Harsh Sharma , Uma Divakaran

An elementary excitation in an aggregate of coupled particles generates a collective excited state. We show that the dynamics of these excitations can be controlled by applying a transient external potential which modifies the phase of the…

Quantum Physics · Physics 2013-06-14 Ping Xiang , Marina Litinskaya , Evgeny A. Shapiro , Roman V. Krems

Pumping of charge (Q) in a closed ring geometry is not quantized even in the strict adiabatic limit. The deviation form exact quantization can be related to the Thouless conductance. We use Kubo formalism as a starting point for the…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 Doron Cohen

Adiabatic reverse annealing (ARA) is an improvement to conventional quantum annealing (QA) that uses an initial guess at the desired ground state to circumvent problematic phase transitions. Despite encouraging results in the closed-system…

Quantum Physics · Physics 2025-11-24 An Le , Christopher L. Baldwin

Adiabatic pumping is a fundamental concept in the time-dependent transport of mesoscopic devices. To maximize pumping performance, i.e., the amount of pumping per unit time, it is necessary to carefully manage the driving speed, which…

Mesoscale and Nanoscale Physics · Physics 2020-06-24 Masahiro Hasegawa , Takeo Kato

In a quantum system with a smoothly and slowly varying Hamiltonian, which approaches a constant operator at times $t\to \pm \infty$, the transition probabilities between adiabatic states are exponentially small. They are characterized by an…

Quantum Physics · Physics 2009-10-31 Michael Wilkinson , Michael A. Morgan

We study quantum heat exchange in a multi-state impurity coupled to two thermal reservoirs. Allowing for strong system-bath interactions, we show that a steady-state heat exchange fluctuation theorem holds, though the dynamical processes…

Statistical Mechanics · Physics 2015-05-28 L. Nicolin , D. Segal

We study charge and spin transport through an interacting quantum wire, caused by backscattering off an effective impurity potential with a periodic time-dependence. The adiabatic regime of this pump for charge and spin is shown to depend…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Prashant Sharma , Claudio Chamon

The nonadiabatic quantum Vlasov equation in spinor QED is derived, and its relation to the well-known adiabatic one is established by three methods. One is by an explicitly analytical expression, the second is by the Dirac equation in the V…

High Energy Physics - Theory · Physics 2024-03-19 Z. L. Li , Y. J. Li

We give a gauge description of the adiabatic charge pumping in closed systems, both in Abelian and non-Abelian processes, and by means of asymptotic Wilson loops in a suitable parameter manifold. Our geometric formulation provides new…

Mesoscale and Nanoscale Physics · Physics 2015-03-17 R. Leone

We decompose the quantum adiabatic evolution as the products of gauge invariant unitary operators and obtain the exact nonadiabatic correction in the adiabatic approximation. A necessary and sufficient condition that leads to adiabatic…

Quantum Physics · Physics 2016-05-12 Zhen-Yu Wang , Martin B. Plenio

We propose a method to dynamically generate and control the flow of spin-entangled electrons, each belonging to a spin-singlet, by means of adiabatic quantum pumping. The pumping cycle functions by periodic time variation of localized…

Quantum Physics · Physics 2016-09-08 Kunal K. Das , Sungjun Kim , Ari Mizel

Periodically driven quantum dots can act as counterparts of cyclic thermal machines at the nanoscale. In the slow-driving regime of geometric pumping, such machines have been shown to operate in analogy to a Carnot cycle. For larger driving…

Mesoscale and Nanoscale Physics · Physics 2023-09-07 Juliette Monsel , Jens Schulenborg , Janine Splettstoesser

Transition of molecular hydrogen to atomic ionized state with increase of temperature and pressure poses still unresolved problems for experimental methods and theory. Here we analyze the dynamics of this transition and show its…

Materials Science · Physics 2020-03-25 Ilya D. Fedorov , Nikita D. Orekhov , Vladimir V. Stegailov

By combining Floquet theory with Green's function formalism, we present non-adiabatic quantum spin and charge pumping through a zigzag ferromagnetic graphene nanoribbon including a double-barriers structure driven weakly by two local $ac$…

Mesoscale and Nanoscale Physics · Physics 2015-09-25 Hosein Cheraghchi

We present a diagrammatic real-time approach to adiabatic pumping of electrons through interacting quantum dots. Performing a systematic perturbation expansion in the tunnel-coupling strength, we compute the charge pumped through a…

Mesoscale and Nanoscale Physics · Physics 2016-08-16 Janine Splettstoesser , Michele Governale , Jürgen König , Rosario Fazio
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