11 Sep New Technique Brings Quantum Computer Closer to Reality
Researchers at the University of Bristol’s Centre for Quantum Photonics have collaborated with scientists from Delft University (Netherlands) and Heriot-Watt University (Scotland) to develop a process to manufacture functioning quantum chips from silicon. Silicon is the same material used to produce microprocessors for PCs, laptops, and smart phones.
Traditional computing relies on a ‘bit’ as the basic unit for coding computer information. A bit has a value of either 0 or 1. Quantum computing replaces a bit with a ‘qubit’. Like a bit, a qubit can also have two possible values – 0 or 1. However, a qubit has the ability to exist in superposition or contain both values.
Consequently, a quantum processor can perform mathematical computations on both states— 0 and 1, at once.
Since 1981, when physicist Richard Feynman postulated the idea of “tiny computers obeying quantum mechanical laws,” progress in the field has been limited to small steps.
Conventional computers manipulate electrical currents to process data. The circuits on quantum chips utilize quantum effects, such as superposition and entanglement to perform operations. Entanglement refers to the ability of particles, such as electrons, photons, or qubits, to interact with each other regardless of their distance apart. Quantum chips control photons (single particles of light) to execute computations.
A computer with a two-qubit system performs operations on four values, simultaneously, a three-qubit system computes eight values at the same time, and a four-qubit system processes 16 values concurrently.
Each additional qubit boosts the processing power of a computer exponentially.
Uses Existing Manufacturing Infrastructure
According to Mark Thompson, the Deputy Director of the Centre for Quantum Photonics in the University of Bristol’s Centre Schools of Physics and Electrical & Electronic Engineering, manufacturers would have the ability to fabricate quantum chips with “circuits over 1,000 times smaller than current glass-based technologies.”
The process uses the same manufacturing practices already in place for standard microelectronics and is suitable for large-scale manufacturing. In addition, quantum circuits work with the existing fiber optic infrastructure and Internet.
Transitioning from glass-based technologies to silicon-based circuits opens the possibility of developing hybrid processors with both conventional and quantum characteristics. Bristol’s, physics professor Jeremy O’Brien expects integration of the two technologies to happen within the next three to five years.
The new quantum chips will first appear in cellular phones and payment systems — making them more secure. The next application would be the production of mega-fast quantum computers. Quantum computing also has applications in pharmaceuticals, material science, and other fields.