Fault tolerance plays a major role in quantum computer design. As the quantum environment is not stable enough when the information is read from it, better designs with error correcting capability have to be designed to overcome the information loss due to decoherence in quantum circuits. This paper presents one such fault tolerant design using a new reversible gate.

There are quantum algorithms that can efficiently simulate quantum physics, factor large numbers and estimate integrals. As a result, quantum computers can solve otherwise intractable computational problems. One of the main problems of experimental quantum computing is to preserve fragile quantum states in the presence of errors. It is known that if the needed elementary operations (gates) can ...

VLSI technology scaling has spurred a rapid growth in the semiconductor industry. With CMOS device dimensions falling below 100 nm, achieving higher performance and packing more complex functionalities into digital integrated circuits have become easier. However, the scaling trend poses new challenges to design and process engineers. Such challenges include larger process parameter variations a...

Twisted rapid passage is a type of non-adiabatic rapid passage that gives rise to controllable quantum interference effects that were first observed experimentally in 2003. We show that twisted rapid passage sweeps can be used to implement a universal set of quantum gates that operate with high-fidelity. For each gate in the universal set, sweep parameter values are provided which simulations i...

We describe an extension of single-qubit gate randomized benchmarking that measures the error of multiqubit gates in a quantum information processor. This platform-independent protocol evaluates the performance of Clifford unitaries, which form a basis of fault-tolerant quantum computing. We implemented the benchmarking protocol with trapped ions and found an error per random two-qubit Clifford...

Given a gate set S universal for quantum computing, the problem of decomposing a unitary operator U into a circuit over S is known as the synthesis problem. This problem can be solved exactly, if U belongs to the set of circuits generated by S. Otherwise, it can be solved approximately, by finding a circuit U ′ such that ||U ′ −U || < for some chosen precision > 0. The synthesis problem is impo...

Use of independently-driven nano-scale double gate (DG) MOSFETs for low-power analog circuits is emphasized and illustrated. In independent drive configuration, the top gate response of DG-MOSFETs can be altered by application of a control voltage on the bottom gate. We show that this could be a powerful method to conveniently tune the response of conventional CMOS analog circuits especially fo...

In parity preserving reversible circuit, the parity of the input vector must match the parity of the output vector. It renders a wide class of circuit faults readily detectable at the circuit’s outputs. Thus reversible logic circuits that are parity preserving will be beneficial to the development of fault tolerant systems in nanotechnology. This paper presents an efficient realization of well ...

Quantum computation provides great speedup over its classical counterpart for certain problems. One of the key challenges for quantum computation is to realize precise control of the quantum system in the presence of noise. Control of the spin-qubits in solids with the accuracy required by fault-tolerant quantum computation under ambient conditions remains elusive. Here, we quantitatively chara...