The researchers discovered that the perovskites possess two properties necessary to make spintronic devices work – the electrons' spin can be easily controlled and its direction maintained long enough to transport information.
"It's a device that people always wanted to make, but there are big challenges in finding a material that can be manipulated and, at the same time, have a long spin lifetime," said assistant professor Sarah Li.
The material's chemical composition is an unlikely candidate for spintronics, however. The hybrid perovskite inorganic frame is made of heavy elements: the heavier the atom, the easier it is to manipulate the electron spin. But when the atoms are heavy, the spin lifetime is generally short.
To tune the electron spin, the researchers formed a thin film from the hybrid perovskite methyl-ammonium lead iodine and placed it in front of an ultrafast laser that shoots short light pulses 80million times a second.
They split the laser into two beams; the first one hit the film to set the electron spin in the desired direction. The second beam was projected through a series of mirrors before hitting the perovskite film at increasing time intervals to measure how long the electron held the spin in the prepared direction.
They found that the perovskite has a surprisingly long spin lifetime – up to nanosecond. The spin flips many times during one nanosecond, which means a lot information can be easily stored and manipulated during that time.
Once they determined the spin lifetime, the researchers tested how well they could manipulate the spin with a magnetic field.
They found that they could rotate the spin more than 10 turns by exposing the electron to different strengths of magnetic field. The material could therefore process data faster and increase random-access memory.
