搜索结果: 1-15 共查到“物理学 spontaneous”相关记录33条 . 查询时间(0.125 秒)
Scientists have long known the ins and outs of equilibrium thermodynamics. Systems in equilibrium — a stable state of unchanging balance — are governed by a neat set of rules, making them predictable ...
Physicists Observe Spontaneous Mechanical Buckling in Freestanding Graphene
Physicists Spontaneous Mechanical Buckling Freestanding Graphene
2016/9/14
An international team of physicists, led by researchers at the University of Arkansas, has observed spontaneous mechanical buckling in freestanding graphene using scanning tunneling microscopy, indica...
Stimulated coherent spontaneous emission in an FEL with 'quiet' bunches
shot noise reduction controlled microbunching instability laser heater
2012/5/11
For a planar FEL configuration we study stimulated coherent spontaneous emission driven by a gradient of the bunch current in the presence of different levels of noise in bunches. To perform a vast am...
Electron-Dominated Spontaneous Bifurcation of Harris Equilibrium
Electron-Dominated Spontaneous Bifurcation Harris Equilibrium Plasma Physics
2012/5/7
In this letter the spontaneous bifurcation of Harris equilibrium current sheet is reported. The collisionless current bifurcation is simulated by a 2D particle-in-cell approach. Explicit particle adva...
Metallo-dielectric hybrid antennas for ultrastrong enhancement of spontaneous emission
Metallo-dielectric hybrid antennas ultrastrong enhancement of spontaneous emission Optics
2012/5/7
We devise new optical antennas that reduce the excited-state radiative lifetimes of emitters to the order of 100 femtoseconds while maintaining quantum efficiencies of about 80% at a broadband operati...
Observation of Superfluorescence from a Spontaneous Coherence of Excitons in ZnTe Crystal: Evidence for Bose-Einstein Condensation of Excitons?
Superfluorescence Spontaneous Coherence Excitons ZnTe Crystal Bose-Einstein Condensation
2011/7/26
Abstract: Superfluorescence (SF) is the emission from a dense coherent system in population inversion, formed from an initially incoherent ensemble. This is characterised by an induction time (t_D) fo...
PT symmetry and spontaneous symmetry breaking in a microwave billiard
PT symmetry spontaneous symmetry microwave billiard Quantum Physics
2011/7/21
Abstract: We demonstrate the presence of parity-time (PT) symmetry for the non-Hermitian two-state Hamiltonian of a dissipative microwave billiard in the vicinity of an exceptional point (EP). The sha...
Spontaneous crystallization and filamentation of solitons in dipolar condensates
Spontaneous crystallization solitons dipolar condensates
2011/7/15
Abstract: Inter-site interactions play a crucial role in polar gases in optical lattices even in the absence of hopping. We show that due to these long-range interactions a destabilized stack of quasi...
Inhibited spontaneous emission of quantum dots observed in a 3D photonic band gap
3D photonic band gap spontaneous emission
2011/6/8
We present time-resolved emission experiments of semiconductor quantum dots in silicon 3D inverse-woodpile photonic band gap crystals. A systematic study is made of crystals with a range of pore radii...
Spontaneous emission spectrum of a V-type three-level atom in a Fabry–Perot cavity containing left-handed materials
Spontaneous emission spectrum V-type three-level atom Fabry–Perot cavity left-handed materials
2011/3/21
The spontaneous emission of a V-type Zeeman atom in a Fabry–Perot cavity containing left-handed materials(LHMs) is investigated. Because of the strong indirect quantum interference induced by the refo...
Universal routes to spontaneous PT-symmetry breaking in non-hermitian quantum systems
Universal routes spontaneous PT-symmetry non-hermitian quantum systems
2010/11/8
PT-symmetric systems can have a real spectrum even when their Hamiltonian is non-hermitian, but develop a complex spectrum when the degree of non-hermiticity increases. Here we utilize random-matrix t...
Scalar field in nuclear matter: the roles of spontaneous chiral symmetry breaking and nucleon structure
nuclear matter roles of spontaneous chiral symmetry breaking nucleon structure
2010/11/1
Chiral theories with spontaneous symmetry breaking such as the Nambu-Jona-Lasinio (NJL)
model lead to the existence of a scalar mode. We present in a detailed manner how the corresponding low momentu...
Bosonic enhancement of spontaneous emission near an interface
Bosonic enhancement spontaneous emission
2010/11/1
We show how the spontaneous emission rate of an excited two-level atom placed in a trapped Bose-Einstein condensate of ground-state atoms is enhanced by bosonic stimulation. This stimulation depends o...
Cosmology of an asymptotically free scalar field with spontaneous symmetry breaking
asymptotically free scalar spontaneous symmetry breaking
2010/11/1
We solve Einstein’s equation with Robertson-Walker metric as an initial-value problem, using as the source of gravity a Halpern-Huang real scalar field, which was derived from renormalization-group an...
Universal routes to spontaneous PT-symmetry breaking in non-hermitian quantum systems
Universal routes PT-symmetry non-hermitian quantum systems
2010/11/1
PT-symmetric systems can have a real spectrum even when their Hamiltonian is non-hermitian, but develop a complex spectrum when the degree of non-hermiticity increases. Here we utilize random-matrix ...