Robert Alicki

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The thermalization process of the 2D Kitaev model is studied within the Markovian weak coupling approximation. It is shown that its largest relaxation time is bounded from above by a constant independent of the system size and proportional to exp(2∆/kT ) where ∆ is an energy gap over the 4fold degenerate ground state. This means that the 2D Kitaev model is(More)
The rate of temperature decrease of a cooled quantum bath is studied as its temperature is reduced to absolute zero. The third law of thermodynamics is then quantified dynamically by evaluating the characteristic exponent ζ of the cooling process dT(t)/dt∼-T^{ζ} when approaching absolute zero, T→0. A continuous model of a quantum refrigerator is employed(More)
We prove continuity of quantum mutual information S(ρ12| ρ2) with respect to the uniform convergence of states and obtain a bound which is independent of the dimension of the second party. This can, e.g., be used to prove the continuity of squashed entanglement. A, generally mixed, state of a bipartite system is given by a density matrix ρ on a Hilbert(More)
We develop dynamical non-Markovian description of quantum computing in weak coupling limit, in lowest order approximation. We show that the long-range memory of quantum reservoir (such as the 1/t one exhibited by electromagnetic vacuum) produces strong interrelation between structure of noise and quantum algorithm, implying nonlocal attacks of noise. This(More)
Abstract: We compute rigorously the ground and equilibrium states for Kitaev’s model in 2D, both the finite and infinite version, using an analogy with the 1D Ising ferromagnet. Next, we investigate the structure of the reduced dynamics in the presence of thermal baths in the Markovian regime. Special attention is paid to the dynamics of the topological(More)
In traditional thermodynamics the Carnot cycle yields the ideal performance bound of heat engines and refrigerators. We propose and analyze a minimal model of a heat machine that can play a similar role in quantum regimes. The minimal model consists of a single two-level system with periodically modulated energy splitting that is permanently, weakly,(More)
The recently developed technique combining the weak-coupling limit with the Floquet formalism is applied to a model of a two-level atom driven by a strong laser field and weakly coupled to heat baths. First, the case of a single electromagnetic bath at zero temperature is discussed and the formula for resonance fluorescence is derived. The expression(More)
Motivated by the recent interest in thermodynamics of micro- and mesoscopic quantum systems we study the maximal amount of work that can be reversibly extracted from a quantum system used to temporarily store energy. Guided by the notion of passivity of a quantum state we show that entangling unitary controls extract in general more work than independent(More)