We present the quantum phase diagram of a superconducting quantum dots array. Superconducting quantum dots are connected through Josephson junctions. We study the effect of finite-range Josephson coupling and also finite-range interactions between the dots. Our field-theoretical study predicts different kinds of phase near the charge degeneracy point. We predict two different kinds of repulsive Luttinger liquid phase and also the possibilities of different density wave instabilities from the inter-play of long-range interaction between the dots and Cooper pair density. We observe different multicritical points with interesting phases.We present the quantum phase diagram of a superconducting quantum dots array. Superconducting quantum dots are connected through Josephson junctions. We study the effect of finite-range Josephson coupling and also finite-range interactions between the dots. Our field-theoretical study predicts different kinds of phase near the charge degeneracy point. We predict two different kinds of repulsive Luttinger liquid phase and also the possibilities of different density wave instabilities from the inter-play of long-range interaction between the dots and Cooper pair density. We observe different multicritical points with interesting phases.

Europhysics Letters (EPL)Dec 1, 20063 citations

Quantum phases of superconducting quantum dot arrays

Sujit Sarkar

We analyze the quantum phases of a superconducting quantum dot array. Superconducting quantum dots are connected through Josephson junction. We study the effect of finite range Josephson coupling and also finite range interactions between the dots. Our field-theoretical study predicts different kinds of phases near the charge degeneracy point. We predict two different kinds of repulsive Luttinger liquid phases originate from different sources: one from the commensurate-incommensurate transition and the other from the $XY$ criticality. Apart from the charge-density wave, we also predict the possibility of dimer-order density wave from the interplay of long-range interaction between the dots and Cooper-pair density. We observe different multicritical points with interesting phases and also two special points. The renormalization group flow diagram also shows many interesting phases.We analyze the quantum phases of a superconducting quantum dot array. Superconducting quantum dots are connected through Josephson junction. We study the effect of finite range Josephson coupling and also finite range interactions between the dots. Our field-theoretical study predicts different kinds of phases near the charge degeneracy point. We predict two different kinds of repulsive Luttinger liquid phases originate from different sources: one from the commensurate-incommensurate transition and the other from the $XY$ criticality. Apart from the charge-density wave, we also predict the possibility of dimer-order density wave from the interplay of long-range interaction between the dots and Cooper-pair density. We observe different multicritical points with interesting phases and also two special points. The renormalization group flow diagram also shows many interesting phases.

Physical Review BJan 26, 200713 citations

Superfluid, Superconducting, and Magnetic Ordering in Mesoscopic Quantum Dots

Alexander F. Andreev

Journal of SuperconductivityFeb 1, 19996 citations

Quantum simulation of Fermi-Hubbard models in semiconductor quantum-dot arrays

Tim Byrnes, Na Young Kim, Kenichiro Kusudo +1 more

We propose a device for studying the Fermi-Hubbard model with long-range Coulomb interactions using an array of coupled quantum dots defined in a semiconductor two-dimensional electron-gas system. Bands above the lowest energy band are used to form the Hubbard model, so that a high average electron density may be used to implement the device. We find that depending on the average electron density, the system is well described by a one- or two-band Hubbard model. Our device design enables the control of the ratio of the Coulomb interaction to the kinetic energy of the electrons independently to the filling of the quantum dots, such that a large portion of the Hubbard phase diagram may be probed. Estimates of the Hubbard parameters suggest that a metal-Mott insulator quantum phase transition and a $d$ -wave superconducting phase should be observable using current technologies.We propose a device for studying the Fermi-Hubbard model with long-range Coulomb interactions using an array of coupled quantum dots defined in a semiconductor two-dimensional electron-gas system. Bands above the lowest energy band are used to form the Hubbard model, so that a high average electron density may be used to implement the device. We find that depending on the average electron density, the system is well described by a one- or two-band Hubbard model. Our device design enables the control of the ratio of the Coulomb interaction to the kinetic energy of the electrons independently to the filling of the quantum dots, such that a large portion of the Hubbard phase diagram may be probed. Estimates of the Hubbard parameters suggest that a metal-Mott insulator quantum phase transition and a $d$-wave superconducting phase should be observable using current technologies.

arXiv:0711.2841Physical Review BAug 25, 200892 citations

Quantum phase analysis of 1D superconducting quantum dot lattice using extended Bose-Hubbard model

Manoranjan Kumar, Saubhik Sarkar, S. Ramasesha

The European Physical Journal BNov 3, 20091 citation

XY

criticality. Apart from the charge-density wave, we also predict the possibility of dimer-order density wave from the interplay of long-range interaction between the dots and Cooper-pair density. We observe different multicritical points with interesting phases and also two special points. The renormalization group flow diagram also shows many interesting phases.

d

-wave superconducting phase should be observable using current technologies.