Periodic Reporting for period 3 - FANO (Fano Photonics)
Periodo di rendicontazione: 2022-09-01 al 2024-02-29
A new class of devices exploiting Fano resonances and with important applications in information technology is suggested.
Typically, the resonance of a system is described by a frequency and a lifetime, leading to a Lorentzian lineshape function. If
the system instead involves interference between a discrete resonance and a continuum, a Fano lineshape appears with
fundamentally different characteristics. Here, the Fano resonance is used to make a novel integrated mirror, enabling
realization of Fano lasers, Fano switches and quantum Fano devices. These devices challenge well-accepted paradigms for
photonic devices. The goals of the project are to demonstrate a laser with modulation bandwidth greatly exceeding all
existing lasers; a nanolaser with linewidth three orders of magnitude smaller than existing nanocavity lasers; and a switch
that operates at femtojoule energies and provides gain. Such devices are important for realizing high-speed optical
interconnects and networks between and within chips. An increasing fraction of the global energy consumption is being used
for data communication, and photonics operating at very high data rates with ultra-low energy per bit has been identified as a
key technology to enable a sustainable growth of capacity demands. Existing device designs, however, cannot just be
scaled down to reach the goals for next-generation integrated devices. The Fano mirror will also be used to demonstrate
control at the single-photon level, which will enable high-quality on-demand single-photon sources, which are much
demanded devices in photonic quantum technology. These devices all rely on the unique properties of the Fano mirror,
which provides a new resource for ultrafast dynamic control, noise suppression and ultra-low energy operation. Using
photonic crystal technology the project will achieve its goals in a concerted effort involving development of new theory, new
nanofabrication techniques and advanced experiments.
Typically, the resonance of a system is described by a frequency and a lifetime, leading to a Lorentzian lineshape function. If
the system instead involves interference between a discrete resonance and a continuum, a Fano lineshape appears with
fundamentally different characteristics. Here, the Fano resonance is used to make a novel integrated mirror, enabling
realization of Fano lasers, Fano switches and quantum Fano devices. These devices challenge well-accepted paradigms for
photonic devices. The goals of the project are to demonstrate a laser with modulation bandwidth greatly exceeding all
existing lasers; a nanolaser with linewidth three orders of magnitude smaller than existing nanocavity lasers; and a switch
that operates at femtojoule energies and provides gain. Such devices are important for realizing high-speed optical
interconnects and networks between and within chips. An increasing fraction of the global energy consumption is being used
for data communication, and photonics operating at very high data rates with ultra-low energy per bit has been identified as a
key technology to enable a sustainable growth of capacity demands. Existing device designs, however, cannot just be
scaled down to reach the goals for next-generation integrated devices. The Fano mirror will also be used to demonstrate
control at the single-photon level, which will enable high-quality on-demand single-photon sources, which are much
demanded devices in photonic quantum technology. These devices all rely on the unique properties of the Fano mirror,
which provides a new resource for ultrafast dynamic control, noise suppression and ultra-low energy operation. Using
photonic crystal technology the project will achieve its goals in a concerted effort involving development of new theory, new
nanofabrication techniques and advanced experiments.
Work has been performed on the three main classes of structures identified in the application, with the following main results achieved:
Within Fano lasers it has been shown that by exploiting a bound state in the continuum, significant reduction of the quantum-limited linewidth can be achieved. Our Fano laser thus holds the world record of narrow linewidth among all microlasers and nanolasers. It has also been theoretically shown that Fano lasers are very robust towards optical feedback, which is very important for application of these sources in integrated photonics. It was also shown that Fano lasers may be promising devices for neuromorphic computing since they can implement nonlinear thresholding. Furthermore it was experimentally demonstrated that Fano lasers can operate in the dynamical regime of cavity dumping, which opens new possibilities for short pulse generation and efficient intensity modulation
Within Fano switches, it was shown that nonlinear effects in the nanocavity of the Fano structure can be used to perform nonlinear filtering of the signal itself. It was also demonstrated experimentally that dual-mode structures can be used to eliminate cross-talk in wavelength conversion. Unexpectedly, it was found that linear filtering using Fano structures can be used to realize a coherent receiver for integrated photonics. A patent application was submitted and an ERC Proof-of-Concept grant was secured to explore the commercial potential.
Within quantum Fano devices, it was theoretically shown that a Fano cavity can be used to reduce phonon-induced decoherence in single-photon sources. A major merit of the work, is the establishment of a rather general framework to efficiently model cavity QED effects in Fano cavities. A comprehensive theoretical model was also established to investigate the dynamical properties of few-photon Fano switches. It was shown that the quantum regime has very rich dynamics. The switching behaviour cannot be described in the same way as for classical switching, but rather four-wave mixing effects play an important role.
Within Fano lasers it has been shown that by exploiting a bound state in the continuum, significant reduction of the quantum-limited linewidth can be achieved. Our Fano laser thus holds the world record of narrow linewidth among all microlasers and nanolasers. It has also been theoretically shown that Fano lasers are very robust towards optical feedback, which is very important for application of these sources in integrated photonics. It was also shown that Fano lasers may be promising devices for neuromorphic computing since they can implement nonlinear thresholding. Furthermore it was experimentally demonstrated that Fano lasers can operate in the dynamical regime of cavity dumping, which opens new possibilities for short pulse generation and efficient intensity modulation
Within Fano switches, it was shown that nonlinear effects in the nanocavity of the Fano structure can be used to perform nonlinear filtering of the signal itself. It was also demonstrated experimentally that dual-mode structures can be used to eliminate cross-talk in wavelength conversion. Unexpectedly, it was found that linear filtering using Fano structures can be used to realize a coherent receiver for integrated photonics. A patent application was submitted and an ERC Proof-of-Concept grant was secured to explore the commercial potential.
Within quantum Fano devices, it was theoretically shown that a Fano cavity can be used to reduce phonon-induced decoherence in single-photon sources. A major merit of the work, is the establishment of a rather general framework to efficiently model cavity QED effects in Fano cavities. A comprehensive theoretical model was also established to investigate the dynamical properties of few-photon Fano switches. It was shown that the quantum regime has very rich dynamics. The switching behaviour cannot be described in the same way as for classical switching, but rather four-wave mixing effects play an important role.
The results on narrow-linewidth Fano lasers is considered to be a major breakthrough (published in Nature Photonics). It demonstrates a viable approach to realizing microlasers and nanolasers with ultra-narrow linewidth.
The experimental results on dynamical control of Fano lasers are also considered to be very promising, representing the first such demonstration for microlasers, and are expected to lead to breakthroughs on the efficient and fast dynamical modulation of microlasers.
We expect soon to demonstrate, for the first time, an electrically-injected Fano laser. The next step will be the electrical modulation of the Fano laser, which is challenging but still considered feasible.
The activities on quantum effects in Fano cavities will, guided by the theoretical model, be focused on experimental demonstration of a single emitter in a Fano cavity and its properties.
The experimental results on dynamical control of Fano lasers are also considered to be very promising, representing the first such demonstration for microlasers, and are expected to lead to breakthroughs on the efficient and fast dynamical modulation of microlasers.
We expect soon to demonstrate, for the first time, an electrically-injected Fano laser. The next step will be the electrical modulation of the Fano laser, which is challenging but still considered feasible.
The activities on quantum effects in Fano cavities will, guided by the theoretical model, be focused on experimental demonstration of a single emitter in a Fano cavity and its properties.