Ci Lei

Molecular electronics device modeling for system design

We have used the Breit-Wigner resonance formula to model a class of molecular electronics devices with the aim to establish an abstract model for a molecular electronic device that can be used in a general cross bar architecture of future nanoelectronic systems. We show that the molecular I-V curves can be characterized by a very small number of variables including the couplings between the contact and leads.

Application of Molecular Electronics Devices in Digital Circuit Design

The Breit-Wigner resonance formula is used to model a class of molecular electronic devices, in order to establish an abstract model for exploration of their applicability in future nanoelectronic systems. The model is used to characterize molecular device I-V curves in terms of the coupling between the molecule and the leads, and demonstrate digital circuit functionality. Circuit metrics such as noise margin, speed and power are investigated.

Design of robust molecular electronic circuits

A compact model for molecular electronic devices that considers the accumulation of charge on the molecule by an equivalent capacitive charging process which is suitable for transient analyses is presented. The model is used to examine the viability of molecular devices in future electronics applications. Further Monte Carlo simulations are carried out to examine digital behaviour in the face of a statistical spread in device characterising parameters, revealing relatively robust circuit behaviour and showcasing the models capability to relate fundamental physical constants governing the quantum mechanical behavior of the device to abstract figures of merit.

Applications and implementation of Fourier multiport devices

Fourier multiport devices in which the creation and annihilation operators at the output are related to those at the input through a finite Fourier transform are studied. A general method for the calculation of the output for arbitrary input states is presented. The case of a squeezed state at one of the inputs and vacua at all other inputs is discussed. In the case of thermal states at the input, the device can be used as a thermometer. A factorization technique inspired by the fast Fourier transform leads to a substantial reduction in the number of beam splitters that are required for the experimental implementation of these devices.

Analytic and contour representations in the unit disk based on SU(1,1) coherent states

A contour representation in the unit disk based on SU(1,1) coherent states is introduced. The scalar product is given by a contour integral. The regions of convergence of the functions representing ket and bra states are studied. An analytic representation in the unit disk is also considered, where the scalar product is represented by an integral over the unit disk, with the Lobachevsky measure. Various relations which connect these analytic functions with other phase-space quantities are derived.

An analytic function approach to weak mutually unbiased bases

Quantum systems with variables in

Analytic representations with theta functions for systems on ℤ(d) and on .

{\mathbb Z}(d)

Selective correlations in finite quantum systems and the Desargues property

are considered, and three different structures are studied. The first is weak mutually unbiased bases, for which the absolute value of the overlap of any two vectors in two different bases is

A triality between weak mutually unbiased bases, zeros of their analytic representations, and finite geometries

1/\sqrt{k}

The groupoid of bifractional transformations

(where