Reply to "Common on `Superfluidity in the interior-gap states'"
We show that the recent Comment by Liu and Wilczek (cond-mat/0304632) on our work (PRA 67, 053603) is incorrect.
cond-mat↗
arXiv subjects
Sungkit Yip
Publications and source records attributed to Sungkit Yip.
Superfluidity in the interior-gap states
We investigate superfluidity in the interior-gap states proposed by Liu and Wilczek. At weak coupling, we find the {\em gapless} interior-gap state unstable in physically accessible regimes of the parameter space, where the superfluid density is shown to be always negative. We therefore conclude that the spatially-uniform interior-gap phase is extremely unstable unless it is fully gapped; in this case, however, the state is rather similar to conventional BCS states.
cond-mat↗
Pairing of Fermions with Arbitrary Spin
Motivated by the recent success of optical trapping of alkali Bose condensate, we have studied the superfluid state of optically trapped alkali fermions, which can have Cooper pairs with total spin $J\geq 2$. In this paper, we shall discuss the general structure of these large spin Cooper pairs and their close relation with singlet Cooper pairs with non-zero orbital angular momentum. We also present the exact solution for the J=2 pairing which shows a surprising change of ground state as the spin $f$ of the constituent fermion increases.
cond-mat↗
Pinhole junctions in d-wave superconductors
We present a self consistent treatment of pinhole junctions in $d_{x^2-y^2}$ superconductors. The current-phase relation $j_s(χ)$ is studied at different temperatures and at different angles $α$ between the crystal $\hat a$-axis and the junction (surface) normal. We show that the critical current of a junction can be reduced by pair-breaking effects at the separation. We also study the Josephson energy of a pinhole as a function of the phase difference across the junction. In particular are mapped the positions of the energy minima $χ_{min}$ at different temperatures as functions of ($α_L,α_R$), the crystal orientations of the left and right superconductors. With decreasing temperature there is an increasing range of crystal orientations where $χ_{min}$ varies continuously from 0 to $π$.
cond-mat.supr-con↗
Conductance Anomalies for Normal-Metal-Insulator-Superconductor Contacts
This paper considers the conductance through a dirty junction between a normal conductor and a superconductor with an insulating barrier. It is shown that for large barrier resistances there is a relative enhancement of the conductance near zero voltage, whereas for low barrier resistance this anomaly appears at finite voltage.
cond-mat↗