| Literature DB >> 28211704 |
C M Quintana1, Yu Chen2, D Sank2, A G Petukhov3, T C White2, Dvir Kafri4, B Chiaro1, A Megrant2, R Barends2, B Campbell1, Z Chen1, A Dunsworth1, A G Fowler2, R Graff2, E Jeffrey2, J Kelly2, E Lucero2, J Y Mutus2, M Neeley2, C Neill1, P J J O'Malley1, P Roushan2, A Shabani4, V N Smelyanskiy4, A Vainsencher2, J Wenner1, H Neven4, John M Martinis1,2.
Abstract
By analyzing the dissipative dynamics of a tunable gap flux qubit, we extract both sides of its two-sided environmental flux noise spectral density over a range of frequencies around 2k_{B}T/h≈1 GHz, allowing for the observation of a classical-quantum crossover. Below the crossover point, the symmetric noise component follows a 1/f power law that matches the magnitude of the 1/f noise near 1 Hz. The antisymmetric component displays a 1/T dependence below 100 mK, providing dynamical evidence for a paramagnetic environment. Extrapolating the two-sided spectrum predicts the linewidth and reorganization energy of incoherent resonant tunneling between flux qubit wells.Year: 2017 PMID： 28211704 DOI： 10.1103/PhysRevLett.118.057702
Source DB: PubMed Journal: Phys Rev Lett ISSN： 0031-9007 Impact factor: 9.161