Researchers have successfully developed the world’s first electrically driven perovskite laser, a breakthrough that solves a challenge that has persisted for more than a decade in the field of optoelectronics. A team from Zhejiang University created the device using an innovative dual-cavity design that integrates two distinct optical microcavities into a single, vertically stacked structure. This achievement marks a significant milestone, as previous attempts to create such a laser were hindered by material instability and the need for impractically high electrical currents.
The new semiconductor laser demonstrates performance metrics that significantly surpass existing technologies, particularly state-of-the-art organic lasers. It operates with a threshold current an order of magnitude lower than its counterparts and exhibits superior operational stability and the capacity for high-speed modulation. This combination of efficiency and control opens promising new avenues for applications in on-chip optical data transmission, advanced computing, integrated photonics, and even wearable biomedical devices. The design principle, which effectively couples a light-emitting component with a lasing component in a compact form, provides a viable path forward for a technology that had been stalled by fundamental barriers.
A Long-Standing Scientific Challenge
For years, scientists have recognized the immense potential of perovskite semiconductors as a laser material. These materials are known for their tunable emission spectra, allowing them to produce various colors of light, and they demonstrate extremely low laser emission thresholds when stimulated by an external light source, a process known as optical pumping. However, translating this potential into a device that could be powered directly by electricity has been the greatest challenge in the field, a goal pursued by numerous research groups worldwide.
The primary obstacles were rooted in both material science and device engineering. Fabricating high-quality perovskite single crystals within the necessary microstructures proved to be a persistent difficulty. Furthermore, the intense electrical currents needed to induce lasing in perovskite materials would typically degrade the material, leading to device failure. These fundamental issues required a complete rethinking of the device architecture to circumvent the damaging effects of direct, high-current electrical pumping while still delivering enough energy to stimulate the lasing action.
The Novel Dual-Cavity Solution
To overcome these challenges, the Zhejiang University team invented an integrated, dual-cavity structure. This design cleverly separates the electrical excitation phase from the lasing phase by assigning these tasks to two specialized, optically coupled subunits within the same device. The architecture is complex, featuring a vertically stacked multilayer structure, but its operating principle is straightforward and highly effective.
Integrating Power and Quality
The first component of the design is a high-power microcavity perovskite light-emitting diode (LED) subunit. This section is built to withstand electrical pulses and efficiently generate intense, non-lasing light. The second component is a high-quality, low-threshold perovskite single-crystal microcavity subunit, which is optimized for laser emission but is not subjected to direct electrical current. The two microcavities are engineered to be optically coupled with a high efficiency of 82.7%, ensuring that most of the light produced by the LED is transferred to the lasing crystal.
How the Device Operates
When electrical pulses are applied to the device, they are directed only to the robust microcavity LED subunit. This subunit produces a peak radiant exitance of approximately 2.5 x 10⁴ mW/cm², which is equivalent to an exceptionally high radiance of about 2.0 x 10⁵ W/sr/m². This concentrated optical power is then efficiently delivered into the adjacent single-crystal perovskite microcavity. This flood of photons from the LED acts as an integrated pumping source, providing the energy needed to support the lasing action within the single-crystal cavity without causing the material degradation associated with direct electrical current.
Performance and Benchmarks
The dual-cavity perovskite laser demonstrated significant technological potential through rigorous testing, achieving performance metrics that set new standards for electrically powered semiconductor lasers of its type. The results show a device that is not only highly efficient but also stable and fast, confirming the viability of the integrated design for practical applications.
Unprecedented Low Threshold
A key performance indicator for any laser is its threshold current, the minimum current density required to begin lasing. The new device features a lasing threshold of just 92 A/cm², with an average across devices of 129 A/cm². This is an order of magnitude lower than the threshold of the best-performing electrically driven organic semiconductor lasers, representing a substantial leap in efficiency. This lower energy requirement is a critical factor for developing low-power, compact optoelectronic technologies.
Stability and Speed
Beyond its low threshold, the laser also showed superior operational stability compared to organic lasers. Under pulsed excitation conditions, it demonstrated an operational half-life of 1.8 hours. While the researchers acknowledge this lifespan remains relatively short for some applications, it is a significant improvement and a promising foundation for future work. Furthermore, the device can be rapidly modulated by electrical pulses, achieving a bandwidth of 36.2 MHz. This high-speed switching capability is essential for applications like optical data transmission, where it allows for the efficient encoding of digital information.
The Research Team and Publication
This groundbreaking work was conducted by a research team at Zhejiang University. The project was led by Professor Di Dawei, Deputy Director of the International Research Center for Advanced Photonics, alongside Professor Zhao Baodan and Dr. Zou Chen. Zou Chen is also credited as the first author of the paper detailing the findings. The primary affiliated institutions include the university’s College of Optical Science and Engineering, the State Key Laboratory of Extreme Optical Technology and Instruments, and the Haining International Joint College. The research findings were published in the peer-reviewed scientific journal Nature under the title “Electrically driven lasing from a dual-cavity perovskite device.”
Future Applications and Next Steps
The successful demonstration of this laser opens the door to a wide range of technological applications. Its high-speed modulation capabilities make it a strong candidate for use in optical data transmission and on-chip computing. It could also serve as a coherent light source in integrated photonic chips and compact wearable devices for biomedical monitoring. Professor Zhao Baodan specifically noted its potential for optical data transmission, while Professor Di Dawei highlighted the achievement as an initial milestone that prepares the team for the challenges ahead.
The researchers are already looking toward the next phase of development. A key goal is to transition from the current “integrated pumping” architecture to a simpler, more compact laser diode structure. Such an advancement would be an important step toward creating more scalable and commercially viable optoelectronic technologies. This breakthrough represents a foundational step, with future innovations expected to further refine the device’s performance, extend its operational lifetime, and expand the potential impact of perovskite lasers across numerous scientific and technological domains.
