Periodic Reporting for period 3 - TWIST (Twisted Perovskites - Control of Spin and Chirality in Highly-luminescent Metal-halide Perovskites)
Okres sprawozdawczy: 2022-04-01 do 2023-09-30
The prospect of transferring chirality from organic molecular to bulk inorganic systems opens various possibilities for new phenomena, such as polarized luminescence or spintronics. The properties of chiral electronic states are scientifically complex, but attractive for applications.
While the opto-electronic properties of semiconductors are controlled by charges, magnetic materials operate by using spins. If new materials can be designed that combine these functionalities, powerful novel applications and large gains in performance are possible, i.e. in opto-spintronics. Yet, existing magnetic semiconductors often show lower optoelectronic quality or work at low temperature. Development of new systems is a scientific challenge due to the required coordination of spins and control of physical properties of excited states, while minimizing defects.
Project TWIST aims to demonstrate novel optically-active materials for ultrafast spin-control and chiral emission, which show the combined properties of ferromagnets and excellent semiconductors for efficient spin-LEDs at room temperature. To achieve this, TWIST will develop new design routes to control spin and chirality in doped metal-halide perovskites (MHPs) with magnetic elements and molecules, also in chiral superstructures.
While the opto-electronic properties of semiconductors are controlled by charges, magnetic materials operate by using spins. If new materials can be designed that combine these functionalities, powerful novel applications and large gains in performance are possible, i.e. in opto-spintronics. Yet, existing magnetic semiconductors often show lower optoelectronic quality or work at low temperature. Development of new systems is a scientific challenge due to the required coordination of spins and control of physical properties of excited states, while minimizing defects.
Project TWIST aims to demonstrate novel optically-active materials for ultrafast spin-control and chiral emission, which show the combined properties of ferromagnets and excellent semiconductors for efficient spin-LEDs at room temperature. To achieve this, TWIST will develop new design routes to control spin and chirality in doped metal-halide perovskites (MHPs) with magnetic elements and molecules, also in chiral superstructures.
We had reported that MHPs are exceptionally bright emitters, which underpins their tolerance to defects and chemical modification, and which recently enabled remarkable doping levels with transition-metals without loss of semiconductor performance. Optical spin-control and chiral emission are further enabled by strong spin-orbit coupling, which can enhance exchange-interactions to raise Curie temperatures towards room temperature. These exceptional properties of MHPs, which have already produced efficient solar cells and LEDs, and provide now a unique opportunity for project TWIST.
We have started with the construction of spectroscopic setups, which enable us to probe spin and excitation dynamics on ultrafast timescales, so that magnetization and spin-transfer dynamics can be resolved. This was supported by special investment of the ERC StG and we have now completed this task.
In parallel, we explored new compounds around the hybrid perovskite semiconductors by introducing chiral organic molecules and transition-metal dopants into the structures. The versatile crystal structure of these materials has resulted in exciting effects for excitation and spin control. We will be continuing this direction based on the insights we gained so far.
We have found that the dynamics and angular momentum polarization of excitations can be controlled by the composition of the newly designed materials. This was evidenced by spectroscopic studies on our newly constructed setups. We are exploring this now in the direction of ultrafast optical control of spins in hybrid semiconductor materials.
We have started with the construction of spectroscopic setups, which enable us to probe spin and excitation dynamics on ultrafast timescales, so that magnetization and spin-transfer dynamics can be resolved. This was supported by special investment of the ERC StG and we have now completed this task.
In parallel, we explored new compounds around the hybrid perovskite semiconductors by introducing chiral organic molecules and transition-metal dopants into the structures. The versatile crystal structure of these materials has resulted in exciting effects for excitation and spin control. We will be continuing this direction based on the insights we gained so far.
We have found that the dynamics and angular momentum polarization of excitations can be controlled by the composition of the newly designed materials. This was evidenced by spectroscopic studies on our newly constructed setups. We are exploring this now in the direction of ultrafast optical control of spins in hybrid semiconductor materials.
TWIST will continue to use state-of-the art optical and electronic techniques to unravel the fundamental mechanisms how magnetic moments, light and chiral states order and interact in hybrid semiconductors. The results of TWIST will aim to enable novel opto-spintronic applications with lower energy consumption and novel functionalities.