Detecting the work statistics through Ramsey-like interferometry

Out-of-equilibrium statistical mechanics is attracting considerable interest due to the recent advances in the control and manipulations of systems at the quantum level. Recently, an interferometric scheme for the detection of the characteristic function of the work distribution following a time-dependent process has been proposed [L. Mazzola et al., Phys. Rev. Lett.110 (2013) 230602]. There, it was demonstrated that the work statistics of a quantum system undergoing a process can be reconstructed by effectively mapping the characteristic function of work on the state of an ancillary qubit. Here, we expand that work in two important directions. We first apply the protocol to an interesting specific physical example consisting of a superconducting qubit dispersively coupled to the field of a microwave resonator, thus enlarging the class of situations for which our scheme would be key in the task highlighted above. We then account for the interaction of the system with an additional one (which might embody an environment), and generalize the protocol accordingly.

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Non-Equilibrium Statistical Mechanics

Atmospheric Turbulence ◽

10.1093/oso/9780199236534.003.0010 ◽

2008 ◽

Author(s):

Adrian F. Tuck

Keyword(s):

Statistical Mechanics ◽

Stokes Equations ◽

Steady States ◽

Time Dependent ◽

Central Feature ◽

Equilibrium Statistical Mechanics ◽

Navier Stokes Equations ◽

Future Evolution ◽

Far From Equilibrium ◽

Non Equilibrium

The Earth’s atmosphere is far from equilibrium; it is constantly in motion from the combined effects of gravity and planetary rotation, is constantly absorbing and emitting radiation, and hosts ongoing chemical reactions which are ultimately fuelled by solar photons. It has fluxes of material and energy across its boundaries with the planetary surface, both terrestrial and marine, and also emits a continual outward flux of infrared photons to space. The gaseous atmosphere is manifestly a kinetic system, meaning that its evolution must be described by time dependent differential equations. The equations doing this under the continuum fluid approximation are the Navier–Stokes equations, which are not analytically solvable and which support many non-linear instabilities. We have also seen that the generation of turbulence is a fundamentally difficult yet central feature of air motion, originating on the molecular scale. Non-equilibrium statistical mechanics may offer insight into which steady states a system far from equilibrium as a result of fluxes and anisotropies may migrate, without the need for detailed solution of the explicit path between the states. However, it does not seem possible to demonstrate mathematically that such steady states exist for the atmosphere. A physical view of the planet’s past and probable future suggests that the past and future evolution of the sun and its outgoing fluxes of energy may mean that the air-water-earth system may never have been or will ever be in a rigorously defined steady state. Also, to the human population, the detailed, time-dependent evolution is what matters in many respects. Nevertheless, non-equilibrium statistical mechanics is a discipline which should be applicable in principle to yield information about approximate steady states. These steady states may as a practical matter be definable from the observational record, for example the ice ages and the intervening periods evident in the geological record, or between states with two differing global average abundances of a radiatively active gas such as carbon dioxide. There has been great progress recently in non-equilibrium statistical mechanics, stemming from recent work on the concept of the maximization of entropy production.

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On the time-dependent formulation of analytical continuation in non-equilibrium statistical mechanics

Physica A Statistical Mechanics and its Applications ◽

10.1016/0378-4371(87)90173-7 ◽

1987 ◽

Vol 141 (2-3) ◽

pp. 403-426 ◽

Cited By ~ 11

Author(s):

P.V. Coveney ◽

Cl. George

Keyword(s):

Statistical Mechanics ◽

Analytical Continuation ◽

Time Dependent ◽

Equilibrium Statistical Mechanics ◽

Non Equilibrium

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How to Erase Quantum Monogamy?

Quantum Reports ◽

10.3390/quantum3010004 ◽

2021 ◽

Vol 3 (1) ◽

pp. 53-67

Author(s):

Ghenadie Mardari

Keyword(s):

Quantum System ◽

Quantum Entanglement ◽

The Other ◽

Arrow Of Time ◽

Quantum Level ◽

Delayed Choice ◽

Other Hand ◽

The One ◽

Quantum Erasure ◽

Non Locality

The phenomenon of quantum erasure exposed a remarkable ambiguity in the interpretation of quantum entanglement. On the one hand, the data is compatible with the possibility of arrow-of-time violations. On the other hand, it is also possible that temporal non-locality is an artifact of post-selection. Twenty years later, this problem can be solved with a quantum monogamy experiment, in which four entangled quanta are measured in a delayed-choice arrangement. If Bell violations can be recovered from a “monogamous” quantum system, then the arrow of time is obeyed at the quantum level.

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