Qubit phase space:SU(n)coherent-statePrepresentations
نویسندگان
چکیده
منابع مشابه
Topological phase for entangled two-qubit states.
Entangled states play a crucial role in quantum physics, ranging from fundamental aspects to quantum information processing. We show here that entangled two-qubit states can also be used to characterize unambiguously the subtlety of the SO(3) rotation group topology. The well known two distinct families of path in this group are put in one-to-one correspondence with cyclic evolutions of these e...
متن کاملPhase control in the vibrational qubit.
In order to use molecular vibrations for quantum information processing one should be able to shape infrared laser pulses so that they can play the role of accurate quantum gates and drive the required vibrational transitions. In this paper we studied theoretically how the relative phase of the optimized transitions affects accuracy of the quantum gates in such a system. Optimal control theory ...
متن کاملFlux noise probed with real time qubit tomography in a Josephson phase qubit.
We measure the dependence of qubit phase coherence and flux noise on inductor loop geometry. While wider inductor traces change neither the flux noise power spectrum nor the qubit dephasing time, increased inductance leads to a simultaneous increase in both. Using our new tomographic protocol for measuring low frequency flux noise, we make a direct comparison between the flux noise spectrum and...
متن کاملUncollapsing of a quantum state in a superconducting phase qubit
We demonstrate in a superconducting qubit the conditional recovery (“uncollapsing”) of a quantum state after a partial-collapse measurement. A weak measurement extracts information and results in a non-unitary transformation of the qubit state. However, by adding a rotation and a second partial measurement with the same strength, we erase the extracted information, effectively canceling the eff...
متن کاملEffect of Entanglement on Geometric Phase for Multi-Qubit States
When a multi-qubit state evolves under local unitaries it may obtain a geometric phase, a feature dependent on the geometry of the state’s projective Hilbert space. A correction term to this geometric phase in addition to the local subsystem phases may appear from correlations between the subsystems. We find this correction term can be characterized completely either by the entanglement or comp...
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: 2008
ISSN: 1050-2947,1094-1622
DOI: 10.1103/physreva.78.052108