The present paper proposes a Surface Plasmon Resonance (SPR) sensor utilizing Twisted Bilayer Graphene (TBG)- Hexagonal Boron Nitride (hBN) heterostructures to enhance the Goos-Hänchen (GH) shift. The study presents a theoretical demonstration of the adjustability of GH shift via tuning the TBG twist angle, the number of TBG layers, and the thickness of hBN, respectively. The two-dimensional twisted bilayer graphene twist angle effectively promotes the sensitivity of the sensor. With a relative twist angle of 76.87°, the sensitivity of this sensor structure is remarkably enhanced to 1.8×108 μm/RIU. The outcomes of this investigation offer a theoretical underpinning for the development of new high-sensitivity biosensors.
We propose a structure that uses surface plasmon resonance (SPR) of two-dimensional (2D) materials to enhance the sensitivity of the biosensor. When the GH shift is used as an interrogation to the biosensor, since SPR can greatly enhance and control the Goos-Hänchen (GH) shift, the biosensor will have excellent sensitivity. Theoretical research results show that by adjusting the structural parameters, a huge GH shift and a sensitivity that is hundreds of times higher than that of ordinary biosensors can be obtained. This will help research in areas such as basic biology and environmental monitoring.
We investigated wavelength conversion for polarization multiplexing signal based on four-wave mixing in a semiconductor optical amplifier. We found that the converted signals endured crosstalk among the pol-muxed channels. We also proposed and demonstrated a wavelength conversion scheme with polarization diversity technique. By utilizing the technique, the converted polarization multiplexing signal can be received without crosstalk. In addition, the performance of the proposed system is numerically analyzed with respect to the bit error rate of the converted signal, different frequency spacing between signal and pump and modulated data rate. The simulation results show that the proposed scheme may be a promising method to realize transparent wavelength conversion for polarization multiplexing signals.
Graphene, due to its linear energy band structure and the Pauli blocking principle, exhibits broadband optical saturable
absorption. We experimentally demonstrated the saturable absorption in graphene with different layers at 800 nm. By
performing the balanced twin-detector method, we are able to characterize the nonlinear optical property of the
as-fabricated different layer graphene samples. Under strong illumination, we find that absorption of graphene decreases
with the increase of incident power, and by fitting the experiment data with theoretical model, the saturable intensity and
the normalized modulation depth is measured to be 7.911 GW/cm2 and 10.6% in 3 layers sample and 2.77 GW/cm2 and
73.6% in monolayer sample, respectively. The experimental result shows that graphene may be a promising saturable
absorber, with the potential laser photonics applications, such as laser mode locker or Q-switcher, at 800 nm band.
Metamaterials (MMs) are artificial structures, which can be engineered to satisfy the prescribed requirements. The most
important difference between an ordinary medium and a MM is that the former has a constant permeability, while the latter
has a dispersive and controllable permeability. MMs can extend the electromagnetic properties of conventional materials,
and the study of the nonlinear propagation of ultrashort pulses in MMs could lead to completely new electronic and optical
devices. In this paper, the research advances on the propagation of electromagnetic pulses in MMs with third-order nonlinear
response are briefly described. Special effort is focused on the typical nonlinear optical phenomena such as modulation
instability, bright and dark solitons.
We propose a novel scheme to generate return-to-zero differential phase-shift keyed (RZ-DPSK) and carrier-suppressed
RZ-DPSK (CSRZ-DPSK) formats based on the differential Mach-Zehnder modulator (DMZM), which can adjust the
operating point of the modulator and control chirp conditions easily. It is more cost-effective due to its simple
configuration.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.