Fundamental Work Cost of Quantum Processes

Faist, Philippe; Renner, Renato

doi:10.1103/physrevx.8.021011

Cited by 66 publications

(132 citation statements)

References 116 publications

(207 reference statements)

Supporting

Mentioning

130

Contrasting

Order By: Relevance

“…More generally, can other forms of asymmetry with respect to a group representation be broadcast? Here we show that this is forbidden by the laws of quantum mechanics, thereby solving certain open problems in the quantum information and thermodynamics literature [6][7][8][9][10]. Connecting to recent results [11], we also show that even weaker forms of broadcasting are allowed by quantum theory only in the * markusm23@univie.ac.at FIG.…”

supporting

confidence: 74%

Coherence and Asymmetry Cannot be Broadcast

Lostaglio

Müller

2019

Phys. Rev. Lett.

View full text Add to dashboard Cite

In the presence of conservation laws, superpositions of eigenstates of the corresponding conserved quantities cannot be generated by quantum dynamics. Thus, any such coherence represents a potentially valuable resource of asymmetry, which can be used, for example, to enhance the precision of quantum metrology or to enable state transitions in quantum thermodynamics. Here we ask if such superpositions, already present in a reference system, can be broadcast to other systems, thereby distributing asymmetry indefinitely at the expense of creating correlations. We prove a no-go theorem showing that this is forbidden by quantum mechanics in every finite-dimensional system. In doing so we also answer some open questions in the quantum information literature concerning the sharing of timing information of a clock and the possibility of catalysis in quantum thermodynamics. We also prove that even weaker forms of broadcasting, of whichÅberg's 'catalytic coherence' is a particular example, can only occur in the presence of infinite-dimensional reference systems. Our results set fundamental limits to the creation and manipulation of quantum coherence and shed light on the possibilities and limitations of quantum reference frames to act catalytically without being degraded. arXiv:1812.08214v2 [quant-ph]

show abstract

supporting

confidence: 74%

Coherence and Asymmetry Cannot be Broadcast

Lostaglio

Müller

2019

Phys. Rev. Lett.

View full text Add to dashboard Cite

show abstract

“…We also study the decay of work fluctuations in the presence of a thermal bath. In this case, fluctuation-free protocols have been extensively studied in the last years within the field of single-shot thermodynamics [5,6,[17][18][19][20][21][22][23][24][25], and our results provide new insights on the mesoscopic regime [23,24,[26][27][28][29], where N is finite and possibly small. Our considerations concern states that are diagonal in the energy basis, as the definition of work fluctuations in coherent systems is subtle and an active area of research [30].…”

Section: Introductionmentioning

confidence: 65%

Collective operations can extremely reduce work fluctuations

Perarnau-Llobet

Uzdin

2019

New J. Phys.

View full text Add to dashboard Cite

We consider work extraction from N copies of a quantum system. When the same work-extraction process is implemented on each copy, the relative size of fluctuations is expected to decay as N 1. Here, we consider protocols where the copies can be processed collectively, and show that in this case work fluctuations can disappear exponentially fast in N. As a consequence, a considerable proportion of the average extractable work  can be obtained almost deterministically by globally processing a few copies of the state. This is derived in the two canonical scenarios for work extraction: (i) in thermally isolated systems, where  corresponds to the energy difference between initial and passive states, known as the ergotropy, and (ii) in the presence of a thermal bath, where  is given by the free energy difference between initial and thermal states.

show abstract

“…To formulate our ideas we adopt a commonplace view in quantum thermodynamics, namely, that work is a central resource that is required to move systems away from freely available thermal equilibrium states [24]-an approach that has staged a diverse range of investigations within the broader field [25][26][27]. In this paradigm, previous research has investigated the work-cost (or gain) of quantum processes [28][29][30][31][32], refrigeration [33,34], or for establishing correlations [35][36][37][38].…”

Section: Tpm Schemementioning

confidence: 99%

Work estimation and work fluctuations in the presence of non-ideal measurements

et al. 2019

View full text Add to dashboard Cite

From the perspective of quantum thermodynamics, realisable measurements cost work and result in measurement devices that are not perfectly correlated with the measured systems. We investigate the consequences for the estimation of work in non-equilibrium processes and for the fundamental structure of the work fluctuations when one assumes that the measurements are non-ideal. We show that obtaining work estimates and their statistical moments at finite work cost implies an imperfection of the estimates themselves: more accurate estimates incur higher costs. Our results provide a qualitative relation between the cost of obtaining information about work and the trustworthiness of this information. Moreover, we show that Jarzynski's equality can be maintained exactly at the expense of a correction that depends only on the system's energy scale, while the more general fluctuation relation due to Crooks no longer holds when the cost of the work estimation procedure is finite. We show that precise links between dissipation and irreversibility can be extended to the non-ideal situation.

show abstract

Fundamental Work Cost of Quantum Processes

Cited by 66 publications

References 116 publications

Coherence and Asymmetry Cannot be Broadcast

Coherence and Asymmetry Cannot be Broadcast

Collective operations can extremely reduce work fluctuations

Work estimation and work fluctuations in the presence of non-ideal measurements

Contact Info

Product

Resources

About