Quantum computers one step closer thanks to BGA chip design

Quantum computers one step closer thanks to BGA chip design

Scientists commonly seem to believe that there is huge potential for the use of quantum computers in

the future. Such computers have the potential to "revolutionize chemistry, biology and material science,"

reports Phys.org. However those trying to develop quantum computers have been hitting development

barriers including an important one which concerns the electrode density of the chip. Georgia Tech

Research Institute (GTRI) and Honeywell International researchers have solved the problem of electrode

density by borrowing ideas from the BGA chip package design.

One of the leading design candidates for a quantum computer chip manipulates individual ions trapped

in a vacuum with laser beams. The qubit density offered by this chip design is limited by the number of

laser electrodes that can be fitted around the chip perimeter. GTRI and Honeywell scientists have

discovered that a ball grid array (BGA) microfabrication can improve the electrode and thus qubit

density of a chip. The new technique was "trapping ions from the very first day," of development.

The team also improved space around the chip perimeter by using trench capacitors and moving

wire connections.

More qubits means the computer can encode, store and access larger amounts of data. Phys.org says a

300 qubit system's quantum state would require 2^ 300 numbers to be described, which is approximately

the same as the number of protons in the known universe. "No amount of Moore's Law scaling will ever

make it possible for a classical computer to process that many numbers," said research head Nicholas Guise.

Now there are plenty of engineering challenges still left to make the BGA project miniaturised enough and

robust enough to form the basis of a quantum computer. In a parallel to how transistors were combined to

form computers these qubit chips need to be able to be combined so many qubits can be produced and

controlled at the same time. While quantum computers are just one step closer, what has been learnt is

still useful for making miniature atomic devices like sensors, magnetometers and chip-scale atomic clocks.