Levitating Nanodiamonds Spin at 1.2 Billion RPM in a Vacuum
Physicists at Purdue University levitated nanoscale diamonds, making them glow and spin at 1.2 billion rpm with lasers. These experiments could greatly advance quantum physics research.
Creating Quantum-Ready Nanodiamonds via High Pressure
The nanodiamonds, with an average width of 750 nanometers, are initially produced under high pressure and temperature. Then, they are irradiated with high-energy electrons to create what is known as a nitrogen-vacancy defect, which can be used to store quantum information.
The team made the nanodiamonds levitate by creating a surface ion trap with a thin gold layer on a sapphire wafer, etched into an “omega” (Ω) shape. When current flows through the gold, it generates an electromagnetic field that levitates the nanodiamond in a vacuum chamber.
Kunhong Shen
We can adjust the voltage to change the direction of rotation,” explained Kunhong Shen, one of the study’s authors. “The levitated diamond can rotate around the z-axis (which is perpendicular to the surface of the ion trap), as shown in the diagram, either clockwise or counterclockwise, depending on our control signal. If we do not apply the control signal, the diamond will spin in all directions, like a ball of yarn.
Achieving Record-Breaking Nanodiamond Spin Rates
In doing so, the team managed to get the nanodiamonds spinning at speeds of up to 1.2 billion rpm. While impressive, this record is far from the fastest— the same group currently holds the record with a nanoscale “dumbbell” that reached an astonishing 300 billion rpm.
Exploring Quantum Gravity with Levitating Nanodiamonds
The nanodiamond study goes beyond breaking records. Green laser illumination reveals electron spin states, while an infrared laser shows their rotation. Comparing these measurements helps scientists understand how the diamonds’ spin affects quantum information.
Imagine tiny diamonds floating in a vacuum,” said Tongcang Li, the study’s lead author. “These diamonds house spin qubits for precise measurements and exploring quantum mechanics’ link to gravity. While past experiments struggled with diamond loss and qubit readings, we successfully levitated a diamond with an ion trap, allowing us to observe and control spin qubits for the first time.
The main question the team hopes to explore is how gravity could be explained in quantum terms, which remains one of the most challenging problems in physics.
Read the original article on: New Atlas
