TY - JOUR
T1 - Nonequilibrium quantum fluctuations of a dispersive medium: Spontaneous emission, photon statistics, entropy generation, and stochastic motion
JF - Physical Review A
Y1 - 2014
A1 - Mohammad F. Maghrebi
A1 - Robert L. Jaffe
A1 - Mehran Kardar
AB - We study the implications of quantum fluctuations of a dispersive medium, under steady rotation, either in or out of thermal equilibrium with its environment. A rotating object exhibits a quantum instability by dissipating its mechanical motion via spontaneous emission of photons, as well as internal heat generation. Universal relations are derived for the radiated energy and angular momentum as trace formulas involving the object's scattering matrix. We also compute the quantum noise by deriving the full statistics of the radiated photons out of thermal and/or dynamic equilibrium. The (entanglement) entropy generation is quantified, and the total entropy is shown to be always increasing. Furthermore, we derive a Fokker-Planck equation governing the stochastic angular motion resulting from the fluctuating back-reaction frictional torque. As a result, we find a quantum limit on the uncertainty of the object's angular velocity in steady rotation. Finally, we show in some detail that a rotating object drags nearby objects, making them spin parallel to its axis of rotation. A scalar toy model is introduced in the first part to simplify the technicalities and ease the conceptual complexities; a detailed discussion of quantum electrodynamics is presented in the second part.
VL - 90
UR - http://arxiv.org/abs/1401.0701v1
CP - 1
J1 - Phys. Rev. A
U5 - 10.1103/PhysRevA.90.012515
ER -
TY - JOUR
T1 - Spontaneous emission by rotating objects: A scattering approach
JF - Physical Review Letters
Y1 - 2012
A1 - Mohammad F. Maghrebi
A1 - Robert L. Jaffe
A1 - Mehran Kardar
AB - We study the quantum electrodynamics (QED) vacuum in the presence of a body rotating along its axis of symmetry and show that the object spontaneously emits energy if it is lossy. The radiated power is expressed as a general trace formula solely in terms of the scattering matrix, making an explicit connection to the conjecture of Zel'dovich [JETP Lett. 14, 180 (1971)] on rotating objects. We further show that a rotating body drags along nearby objects while making them spin parallel to its own rotation axis.
VL - 108
UR - http://arxiv.org/abs/1202.1485v2
CP - 23
J1 - Phys. Rev. Lett.
U5 - 10.1103/PhysRevLett.108.230403
ER -
TY - JOUR
T1 - Casimir force between sharp-shaped conductors
JF - Proceedings of the National Academy of Sciences
Y1 - 2011
A1 - Mohammad F. Maghrebi
A1 - Sahand Jamal Rahi
A1 - Thorsten Emig
A1 - Noah Graham
A1 - Robert L. Jaffe
A1 - Mehran Kardar
AB - Casimir forces between conductors at the sub-micron scale cannot be ignored in the design and operation of micro-electromechanical (MEM) devices. However, these forces depend non-trivially on geometry, and existing formulae and approximations cannot deal with realistic micro-machinery components with sharp edges and tips. Here, we employ a novel approach to electromagnetic scattering, appropriate to perfect conductors with sharp edges and tips, specifically to wedges and cones. The interaction of these objects with a metal plate (and among themselves) is then computed systematically by a multiple-scattering series. For the wedge, we obtain analytical expressions for the interaction with a plate, as functions of opening angle and tilt, which should provide a particularly useful tool for the design of MEMs. Our result for the Casimir interactions between conducting cones and plates applies directly to the force on the tip of a scanning tunneling probe; the unexpectedly large temperature dependence of the force in these configurations should attract immediate experimental interest.
VL - 108
U4 - 6867 - 6871
UR - http://arxiv.org/abs/1010.3223v1
CP - 17
J1 - Proceedings of the National Academy of Sciences
U5 - 10.1073/pnas.1018079108
ER -
TY - JOUR
T1 - Implications of the Babinet Principle for Casimir Interactions
JF - Physical Review D
Y1 - 2011
A1 - Mohammad F. Maghrebi
A1 - Ronen Abravanel
A1 - Robert L. Jaffe
AB - We formulate the Babinet Principle (BP) as a relation between the scattering amplitudes for electromagnetic waves, and combine it with multiple scattering techniques to derive new properties of Casimir forces. We show that the Casimir force exerted by a planar conductor or dielectric on a self- complementary perforated planar mirror is approximately half that on a uniform mirror independent of the distance between them. The BP suggests that Casimir edge effects are anomalously small, supporting results obtained earlier in special cases. Finally, we illustrate how the BP can be used to estimate Casimir forces between perforated planar mirrors.
VL - 84
UR - http://arxiv.org/abs/1103.5395v1
CP - 6
J1 - Phys. Rev. D
U5 - 10.1103/PhysRevD.84.061701
ER -