A research team, led by mechanical engineering researcher Abdelghani Laraoui from Nebraska Engineering, is working towards improving the efficiency and accessibility of quantum computers. By focusing on creating quieter environments and controlling disruptions, the team aims to mitigate decoherence, commonly referred to as “noise,” which hampers the performance of these superfast computers.
Quantum computers have the ability to complete calculations within two minutes that would take thousands of years using classical computing systems. However, their scalability for widespread use is limited due to the requirement of extremely low-temperature environments, which is costly to create.
Laraoui is collaborating with physicist Kapildep Ambal and chemist Jian Wang from Wichita State University. They have been awarded an $800,000 grant from the National Science Foundation’s Expand Capacity in Quantum Information Science and Engineering program to pursue their research over the next three years.
Unlike conventional computing systems, quantum computers utilize superconductive subatomic qubits to store and process information. These qubits enable higher-level tasks, such as simulations and data analysis, to be executed with remarkable speed and precision. However, they perform optimally at extremely cold temperatures around 10 milliKelvin (-459 Fahrenheit).
To overcome the challenge of maintaining such low temperatures, the research team is exploring new quantum materials that can preserve quantum coherence at higher temperatures, specifically above 2 degrees Kelvin (-456 Fahrenheit).
Laraoui’s team will soon receive a cryogenic scanning probe microscope with quantum sensing capabilities, which can operate at temperatures as low as 1.8 Kelvin (-456.4 Fahrenheit), thanks to funding from another NSF grant. The researchers will also use a cryogenic optical microscope, developed in Laraoui’s lab, to observe the behavior of qubits in diamond substrates when exposed to other materials. This technology has been partially supported by the NSF Emergent Quantum Materials and Technologies Center, in which Laraoui serves as a quantum technologies thrust leader.
Expanding the capacity of quantum computers requires the addition of more qubits, similar to adding more bits in classical computers. However, qubit networks pose the challenge of their fragility, as even minor decoherence can hinder their performance, much like a soap bubble losing its unique characteristics upon contact with an object.
Laraoui’s team aims to discover more robust materials, such as ultrathin magnetic films and two-dimensional magnetic materials, to control spin qubits in diamond over longer distances and at higher temperatures.
“The idea is to create a hybrid system that incorporates these spin qubits with elements of a classical system,” explained Laraoui. “By coupling a diamond substrate with spin waves called magnons, which have specific excitations based on particular materials, we can achieve a longer coherence time.”
In essence, increasing the coherence time of quantum computers would allow them to operate in less demanding environments, potentially reducing costs and making them more accessible for a wide range of applications.
Frequently Asked Questions (FAQ)
What is quantum computing?
Quantum computing is a revolutionary field of computing that utilizes superconductive subatomic qubits to store and process information. It can perform complex calculations at an unprecedented speed and precision.
What is decoherence?
Decoherence, also known as “noise,” refers to disruptions in the performance of quantum computers. These disruptions limit their computational abilities and hinder their scalability.
Why do quantum computers require low-temperature environments?
Quantum computers need to operate at extremely low temperatures, around 10 milliKelvin (-459 Fahrenheit), to minimize decoherence and maximize their performance.
How can researchers improve quantum computing performance?
Researchers are exploring new quantum materials that can preserve quantum coherence at higher temperatures. By finding materials that can control and mitigate decoherence, quantum computers can operate at less demanding environments, making them more accessible and cost-effective.
What are the challenges in expanding the capacity of quantum computers?
Expanding the capacity of quantum computers involves adding more qubits. However, quantum systems are fragile, and even slight decoherence can degrade their performance. Overcoming this challenge requires finding more robust materials and techniques to maintain coherence over longer distances.