Kinematic approach to off-diagonal geometric phases of nondegenerate and degenerate mixed states
نویسندگان
چکیده
منابع مشابه
Off-diagonal geometric phases.
We investigate the adiabatic evolution of a set of nondegenerate eigenstates of a parametrized Hamiltonian. Their relative phase change can be related to geometric measurable quantities that extend the familiar concept of Berry phase to the evolution of more than one state. We present several physical systems where these concepts can be applied, including an experiment on microwave cavities for...
متن کامل2 00 3 Geometric phases for non - degenerate and degenerate mixed states
This paper focuses on the geometric phase of general mixed states under unitary evolution. Here we analyze both non-degenerate as well as degenerate states. Starting with the non-degenerate case, we show that the usual procedure of subtracting the dynamical phase from the total phase to yield the geometric phase for pure states, does not hold for mixed states. To this end, we furnish an express...
متن کاملEffects of Entanglement on Off-diagonal Geometric Phases
The effect of entanglement on off-diagonal geometric phases is investigated in the paper. Two spin-1/2 particles in magnetic fields along the y direction are taken as an example. Three parameters (the purity of state r, the mixing angle θ and the relative phase β) are chosen to characterize the initial states. The nodal points at which the usual geometric phases disappear are calculated and ill...
متن کاملGeometric phases for mixed states and decoherence
The gauge invariance of geometric phases for mixed states is analyzed by using the hidden local gauge symmetry which arises from the arbitrariness of the choice of the basis set defining the coordinates in the functional space. This approach gives a reformulation of the past results of adiabatic, non-adiabatic and mixed state geometric phases. The geometric phases are identified uniquely as the...
متن کاملOff-diagonal Mixed State Phases in Unitary Evolution A
Off-diagonal mixed state phases based upon a concept of orthogonality adapted to unitary evolution and a proper normalisation condition are introduced. Some particular instances are analysed and parallel transport leading to the off-diagonal mixed state geometric phase is delineated. A complete experimental realisation of the off-diagonal mixed state geometric phases in the qubit case using pol...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review A
سال: 2005
ISSN: 1050-2947,1094-1622
DOI: 10.1103/physreva.71.032106