Heat Transfer and Torque in Enclosing Cylindrical Configurations with Nonreciprocal Materials

• URL: http://arxiv.org/abs/2608.24967v1
• Date: Tue, 25 Aug 2026 08:11:30 GMT
• Title: Heat Transfer and Torque in Enclosing Cylindrical Configurations with Nonreciprocal Materials
• Abstract summary: Electromagnetic fluctuations can lead to forces, torques, heat currents, and friction in out-of-equilibrium setups.<n>We show that if at least one of two objects is rotationally symmetric, the torque is bounded by heat transfer.<n>We also analyze the conditions for stable levitation of the inner cylinder using the proximity force approximation.
• Score: 3.8500374175119716
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Electromagnetic fluctuations can transfer not only energy but also angular momentum, leading to forces, torques, heat currents, and friction in out-of-equilibrium setups. In enclosing configurations, we show that if at least one of two objects is rotationally symmetric, the torque is bounded by heat transfer, since both arise from photon transfers with angular momentum $\hbar n$ and energy $\hbarω$. With only one object assumed to be rotationally symmetric, it may be possible to obtain a nonzero torque with reciprocal media, but nonreciprocal media are required to break the symmetry between $n$ and $-n$ and produce a nonzero torque if both objects are rotationally symmetric. We then specialize to concentric cylinders with a nonreciprocal dielectric response and use Rytov fluctuational electrodynamics to express heat transfer and torque in terms of an angular-momentum-resolved flux density, $Φ_n(ω)$. We also analyze the conditions for stable levitation of the inner cylinder using the proximity force approximation, in the process obtaining a new analytic formula for the normal Casimir force between dilute plates at different temperatures. Finally, to find the extracted work in a contactless engine setup, we compute the fluctuation-induced friction for a slowly rotating inner cylinder, and we find a bound between torque, friction, and heat transfer. Due to this bound, the efficiency of the heat engine remains bounded by the Carnot limit.

Related papers

• Magnetic long-range order at finite temperature in two-dimensional hyperbolic lattices [45.88028371034407]
  Infrared singularities of gapless Goldstone modes preclude magnetic long-range order at finite temperature in conventional two-dimensional systems.<n>We find that the zero-energy collective modes required by symmetry carry vanishing local spectral weight.<n>We estimate the ordering temperature from the thermal spin-wave correction to the ordered moment.
  arXiv  Detail & Related papers  (2026-06-25T18:00:01Z)
• A Contactless Heat Engine Driven by Nonreciprocal Fluctuation-Induced Torques [3.8500374175119716]
  We describe a contactless heat engine in which quantum and thermal electromagnetic fluctuations act as the working medium.<n>The setup consists of two concentric cylinders held at different temperatures. The inner cylinder stably levitates within the outer one due to repulsive nonequilibrium Casimir forces.
  arXiv  Detail & Related papers  (2026-06-23T18:08:40Z)
• Rotational Vacuum Friction of Nonabsorbing Particles [46.07145155913717]
  A nonabsorbing particle rotating in vacuum can lose angular momentum only by converting mechanical energy into electromagnetic radiation.<n>At zero temperature, the frictional torque scales as $Mpropto7$ with rotation frequency $ Omega$ in anisotropic particles.<n>In contrast, axisymmetric particles are protected against photon-assisted friction regardless of temperature.
  arXiv  Detail & Related papers  (2026-06-23T15:47:57Z)
• Vacuum Torque Without Anisotropy: Switchable Casimir Torque Between Altermagnets [0.0]
  We show that an axially symmetric magnetic field can generate a Casimir torque by inducing an axially asymmetric Casimir energy.<n>Our results identify time-reversal symmetry breaking as a powerful route for engineering both the sign and strength of Casimir torque.
  arXiv  Detail & Related papers  (2026-01-20T19:00:05Z)
• Harnessing Chiral Spin States in Molecular Nanomagnets for Quantum Technologies [44.1973928137492]
  We show that chiral qubits naturally suppress always-on interactions that can not be switched off in weakly coupled qubits.<n>Our findings establish spin chirality engineering as a promising strategy for mitigating always-on interaction in entangling two chiral qubits in molecular quantum technologies.
  arXiv  Detail & Related papers  (2025-01-21T08:23:12Z)
• Thermal Spin Orbit Torque with Dresselhaus Spin Orbit Coupling [0.11838866556981258]
  We obtain a temperature dependent thermal spin-orbit torque in a two dimensional ferromagnet with Dresselhaus spin-orbit coupling. We illustrate them by an example of spin-polarized transport through a ferromagnet with Dresselhaus spin-orbit coupling driven by temperature gradient.
  arXiv  Detail & Related papers  (2023-11-18T10:59:32Z)
• Quantum Torque on a Non-Reciprocal Body out of Thermal Equilibrium and Induced by a Magnetic Field of Arbitrary Strength [0.0]
  A stationary body out of thermal equilibrium with its environment experiences a quantum torque. This arises from the spatially non-symmetric electrical response of the body to its interaction with the non-equilibrium thermal fluctuations of the electromagnetic field.
  arXiv  Detail & Related papers  (2023-09-25T14:51:08Z)
• Control of the Radiative Heat Transfer in a Pair of Rotating Nanostructures [77.34726150561087]
  We investigate the simultaneous transfer of energy and angular momentum in a pair of rotating nanostructures. We demonstrate that, due to the rotation of the nanostructures, the radiative heat transfer between them can be increased, decreased, or even reversed with respect to the transfer that occurs in absence of rotation. This work unravels the unintuitive phenomena arising from the simultaneous transfer of energy and angular momentum in pairs of rotating nanostructures.
  arXiv  Detail & Related papers  (2023-03-02T15:33:50Z)
• Nonequilibrium Casimir effects of nonreciprocal surface waves [52.12351460454646]
  We show that an isotropic dipolar particle in the vicinity of a substrate made of nonreciprocal plasmonic materials can experience a lateral Casimir force and torque. We connect the existence of the lateral force to the asymmetric dispersion of nonreciprocal surface polaritons and the existence of the lateral torque to the spin-momentum locking of such surface waves.
  arXiv  Detail & Related papers  (2021-06-19T23:10:04Z)
• Chemical tuning of spin clock transitions in molecular monomers based on nuclear spin-free Ni(II) [52.259804540075514]
  We report the existence of a sizeable quantum tunnelling splitting between the two lowest electronic spin levels of mononuclear Ni complexes. The level anti-crossing, or magnetic clock transition, associated with this gap has been directly monitored by heat capacity experiments. The comparison of these results with those obtained for a Co derivative, for which tunnelling is forbidden by symmetry, shows that the clock transition leads to an effective suppression of intermolecular spin-spin interactions.
  arXiv  Detail & Related papers  (2021-03-04T13:31:40Z)
• New approach to describe two coupled spins in a variable magnetic field [55.41644538483948]
  We describe the evolution of two spins coupled by hyperfine interaction in an external time-dependent magnetic field. We modify the time-dependent Schr"odinger equation through a change of representation. The solution is highly simplified when an adiabatically varying magnetic field perturbs the system.
  arXiv  Detail & Related papers  (2020-11-23T17:29:31Z)
• Gravity Probe Spin: Prospects for measuring general-relativistic precession of intrinsic spin using a ferromagnetic gyroscope [51.51258642763384]
  An experimental test at the intersection of quantum physics and general relativity is proposed. The behavior of intrinsic spin in spacetime is an experimentally open question. A measurement is possible by using mm-scale ferromagnetic gyroscopes in orbit around the Earth.
  arXiv  Detail & Related papers  (2020-06-16T17:18:44Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.