English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The equilibrium properties of nanoscale systems can deviate significantlyfrom standard thermodynamics due to their coupling to an environment. For thegeneralised $\theta$-angled spin-boson model, we first derive a compact andgeneral form of the classical equilibrium state including environmentalcorrections to all orders. Secondly, for the quantum spin-boson model we prove,by carefully taking a large spin limit, that Bohr's quantum-classicalcorrespondence persists at all coupling strengths. This correspondence givesinsight into the conditions for a coupled quantum spin to be well-approximatedby a coupled classical spin-vector. Thirdly, we demonstrate that previouslyidentified environment-induced 'coherences' in the equilibrium state of weaklycoupled quantum spins, do not disappear in the classical case. Finally, weprovide the first classification of the coupling parameter regimes for thespin-boson model, from weak to ultrastrong, both for the quantum case and theclassical setting. Our results shed light on the interplay of quantum and meanforce corrections in equilibrium states of the spin-boson model, and will helpdraw the quantum to classical boundary in a range of fields, such as magnetismand exciton dynamics.

Quantum-classical correspondence in spin-boson equilibrium states at arbitrary coupling