3,085 research outputs found
Monolithic quantum-dot distributed feedback laser array on silicon
Electrically-pumped lasers directly grown on silicon are key devices
interfacing silicon microelectronics and photonics. We report here, for the
first time, an electrically-pumped, room-temperature, continuous-wave (CW) and
single-mode distributed feedback (DFB) laser array fabricated in InAs/GaAs
quantum-dot (QD) gain material epitaxially grown on silicon. CW threshold
currents as low as 12 mA and single-mode side mode suppression ratios (SMSRs)
as high as 50 dB have been achieved from individual devices in the array. The
laser array, compatible with state-of-the-art coarse wavelength division
multiplexing (CWDM) systems, has a well-aligned channel spacing of 20 0.2 nm
and exhibits a record wavelength coverage range of 100 nm, the full span of the
O-band. These results indicate that, for the first time, the performance of
lasers epitaxially grown on silicon is elevated to a point approaching
real-world CWDM applications, demonstrating the great potential of this
technology
Modeling an Electrically Driven Graphene-Nanoribbon Laser for Optical Interconnects
Graphene has two very important optical properties of population inversion of
electrons, and broadband optical gain. As a result, graphene has potential for
use in lasers and amplifiers. In this work, we presented a quantum master model
and analyzed the properties for the electrically pumped single-AGNR
vertical-cavity surface-emitting lasers (VCSELs) to investigate the lasing
action and laser properties for realistic experimental parameters. A
semiclassical approximation for the output power and laser linewidth is also
derived. The laser threshold power was several orders of magnitude lower than
that currently achievable with semiconductor microlasers. Our results have
demonstrated that a single-AGNR VCSEL can serve as a nanolaser with ultralow
lasing threshold. Implementation of such a GNR-based VCSEL is especially
promising for optical interconnection systems since VCSELs emit low optical
power and single longitudinal mode over a wide wavelength spectral range
through tailoring GNRs.Comment: 5 pages, 4 figures,
http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6458072&tag=
Monolithically Integrated Electrically Pumped Continuous-Wave III-V Quantum Dot Light Sources on Silicon
In this paper, we report monolithically integrated IIIV
quantum dot (QD) light-emitting sources on silicon substrates
for silicon photonics. We describe the first practical InAs/GaAs
QD lasers monolithically grown on an offcut silicon (001) substrate
due to the realization of high quality III-V epilayers on silicon with
low defect density, indicating that the large material dissimilarity
between III-Vs and silicon is no longer a fundamental barrier
limiting monolithic growth of III-V lasers on Si substrates.
Although the use of offcut silicon substrates overcomes the
antiphase boundary (APB) problem, it has the disadvantage of
not being readily compatible with standard microelectronics
fabrication, where wafers with on-axis silicon (001) substrates
are used. We therefore report, to the best of our knowledge, the
first electrically pumped continuous-wave (c.w.) InAs/GaAs QD
lasers fabricated on on-axis GaAs/Si (001) substrates without any
intermediate buffer layers. Based on the achievements described
above, we move on to report the first study of post-fabrication and
prototyping of various Si-based light emitting sources by utilizing
the focused ion beam (FIB) technique, with the intention of
expediting the progress toward large-scale and low-cost photonic
integrated circuits monolithically integrated on a silicon platform.
We compare two Si-based QD lasers with as-cleaved and FIB-made
facets, and prove that FIB is a powerful tool to fabricate integrated lasers on silicon substrates. Using angled facet structures, which
effectively reduce facet reflectivity, we demonstrate Si-based
InAs/GaAs QD superluminescent light emitting diodes (SLDs)
operating under c.w. conditions at room temperature for the first
time. The work described represents significant advances towards
the realization of a comprehensive silicon photonics technology
Low threshold quantum dot lasers directly grown on unpatterned quasi-nominal (001) Si
We report electrically pumped, continuous-wave (cw) InAs/GaAs quantum dot (QD) lasers directly grown on quasi-nominal Si (001) substrates with offcut angle as small as 0.4°. No GaP, Ge buffer layers or substrate patterning is required. An anti-phase boundary free epitaxial GaAs film was grown by metal-organic chemical vapor deposition (MOCVD) with a low threading dislocation density of . Room-temperature cw lasing at ∼1.3 μm has been achieved, with a minimum threshold current density of 34.6 A/cm2 per layer, a maximum operating temperature of 80 °C, and a maximum single facet output power of 52 mW. A comparison of various monolithic III-V hetero-epitaxy on Si solutions is presented. Direct growth on unpatterned quasi-nominal (001) Si may yield the best material quality at the lowest lifecycle cost
Recent progress in epitaxial growth of III-V quantum-dot lasers on silicon substrate
In the past few decades, numerous high-performance silicon (Si) photonic devices have been demonstrated. Si, as a photonic platform, has received renewed interest in recent years. Efficient Si-based III–V quantum-dot (QDs) lasers have long been a goal for semiconductor scientists because of the incomparable optical properties of III–V compounds. Although the material dissimilarity between III–V material and Si hindered the development of monolithic integrations for over 30 years, considerable breakthroughs happened in the 2000s. In this paper, we review recent progress in the epitaxial growth of various III–V QD lasers on both offcut Si substrate and on-axis Si (001) substrate. In addition, the fundamental challenges in monolithic growth will be explained together with the superior characteristics of QDs
Optically pumped 1.3 μm room-temperature InAs quantum-dot micro-disk lasers directly grown on (001) silicon
Direct integration of high-performance laser diodes on silicon will dramatically transform the world of photonics, expediting the progress toward low-cost and compact photonic integrated circuits (PICs) on the mainstream silicon platform. Here, we report, to the best of our knowledge, the first 1.3 μm room-temperature continuous-wave InAs quantum-dot micro-disk lasers epitaxially grown on industrial-compatible Si (001) substrates without offcut. The lasing threshold is as low as hundreds of microwatts, similar to the thresholds of identical lasers grown on a GaAs substrate. The heteroepitaxial structure employed here does not require the use of an absorptive germanium buffer and/or dislocation filter layers, both of which impede the efficient coupling of light from the laser active regions to silicon waveguides. This allows for full compatibility with the extensive silicon-on-insulator (SOI) technology. The large-area virtual GaAs (on Si) substrates can be directly adopted in various mature in-plane laser configurations, both optically and electrically. Thus, this demonstration represents a major advancement toward the commercial success of fully integrated silicon photonics
1.3-μm InAs quantum-dot micro-disk lasers on V-groove patterned and unpatterned (001) silicon
We report comparison of lasing dynamics in InAs quantum dot (QD) micro-disk lasers (MDLs) monolithically grown on V-groove patterned and planar Si (001) substrates. TEM characterizations reveal abrupt interfaces and reduced threading dislocations in the QD active regions when using the GaAs-on-V-grooved-Si template. The improved crystalline quality translates into lower threshold power in the optically pumped continuous-wave MDLs. Concurrent evaluations were also made with devices fabricated simultaneously on lattice-matched GaAs substrates. Lasing behaviors from 10 K up to room temperature have been studied systematically. The analyses spotlight insights into the optimal epitaxial scheme to achieve low-threshold lasing in telecommunication wavelengths on exact Si (001) substrates
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