Low-Power Broadband Thermo-Optic Switch With Weak Polarization Dependence Using a Segmented Graphene Heater

Song, Qian Qian; Chen, Kai Xin; Hu, Zhe

doi:10.1109/jlt.2019.2955511

Cited by 21 publications

(13 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The propagation loss of the MIR light can be reduced to virtually zero, making it suitable for long-wavelength operation. Graphene heaters have been integrated into polymer waveguides [ 50 , 51 ], which can achieve low π phase-shift power consumption ( P π ) of 0.39 mW. However, the low thermal conductivity of polymer leads to a long response time of 92.4 μs, and polymers also become opaque in the mid-infrared waveband.…”

Section: Introductionmentioning

confidence: 99%

Silicon Thermo-Optic Switches with Graphene Heaters Operating at Mid-Infrared Waveband

Zhong

Zhang

et al. 2022

Nanomaterials

View full text Add to dashboard Cite

The mid-infrared (MIR, 2–20 μm) waveband is of great interest for integrated photonics in many applications such as on-chip spectroscopic chemical sensing, and optical communication. Thermo-optic switches are essential to large-scale integrated photonic circuits at MIR wavebands. However, current technologies require a thick cladding layer, high driving voltages or may introduce high losses in MIR wavelengths, limiting the performance. This paper has demonstrated thermo-optic (TO) switches operating at 2 μm by integrating graphene onto silicon-on-insulator (SOI) structures. The remarkable thermal and optical properties of graphene make it an excellent heater material platform. The lower loss of graphene at MIR wavelength can reduce the required cladding thickness for the thermo-optics phase shifter from micrometers to tens of nanometers, resulting in a lower driving voltage and power consumption. The modulation efficiency of the microring resonator (MRR) switch was 0.11 nm/mW. The power consumption for 8-dB extinction ratio was 5.18 mW (0.8 V modulation voltage), and the rise/fall time was 3.72/3.96 μs. Furthermore, we demonstrated a 2 × 2 Mach-Zehnder interferometer (MZI) TO switch with a high extinction ratio of more than 27 dB and a switching rise/fall time of 4.92/4.97 μs. A comprehensive analysis of the device performance affected by the device structure and the graphene Fermi level was also performed. The theoretical figure of merit (2.644 mW−1μs−1) of graphene heaters is three orders of magnitude higher than that of metal heaters. Such results indicate graphene is an exceptional nanomaterial for future MIR optical interconnects.

show abstract

Section: Introductionmentioning

confidence: 99%

Silicon Thermo-Optic Switches with Graphene Heaters Operating at Mid-Infrared Waveband

Zhong

Zhang

et al. 2022

Nanomaterials

View full text Add to dashboard Cite

show abstract

“…2(c) to improve the heat utilization and reduce the electric power consumption further. Assuming that the TO coefficient of the LN material is set at 3.7×10 -5 /K, thermal conductivities of the LN material and the silicon substrate are set at 38 W/(mK) and 163 W/(mK), respectively, and the graphene electrode has a thickness of 0.35 nm, a width of 4 μm, and a total length of 0.5 mm, where the graphene is modeled as a conductive boundary with a complex surface conductivity of 6.08410 -5 -7.51910 -6 i [12], when the applied electric power and depth are set as 151 mW with h3=0, 118.73 mW with h3=0.3 μm, 95.36 mW with h3=5.3 μm, 2.85 mW with br=14 μm, corresponding temperature distributions are calculated at an ambient temperature of 20°C, as displayed in Fig. 4(a) -(d), respectively.…”

Section: Switch Characterizationmentioning

confidence: 99%

“…Secondly, Au contact leads and pads could be formed using lift-off, that is ~200 nm thick Au film pattern formed by spin-coating, photolithography, sputtering or evaporation coating, and chemical etching processes in turn. Thirdly, the graphene electrodes could also be formed by photolithography, and the specific fabrication process could refer to [12]. Finally, the air slots could be formed by various etching processes to remove the adjacent LN thin film, SiO2 layer, and silicon substrate around the tuning regions, such as interference arms in switch units.…”

Section: Switch Characterizationmentioning

confidence: 99%

“…Our structure has an average switching power of ~132.6 mW and insertion loss of <2.34 dB [5]. To reduce the switching power further, we have demonstrated a low-power waveguide switch with the switching power of ~3.3 mW based on a large thermooptic (TO) coefficients polymer waveguide and graphene heater [12]. To make the structure more compact and flexible, we have proposed a continuously tunable delay line based on a highperformance three-dimensional polymer switch driving with graphene heaters [13].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Scalable and Reconfigurable Continuously Tunable Lithium Niobate Thin Film Delay Line Using Graphene Electrodes

Song

2022

IEEE Photonics J.

Self Cite

View full text Add to dashboard Cite

We propose a novel continuously tunable delay line in X-cut lithium niobate thin film driven by graphene electrodes, featuring low power consumption and low half-wave voltagelength product. The use of the graphene electrodes combined with the air slots makes the device quite low power consumption. Our designed device, which has a footprint of 8.9 mm  1.9 mm, is capable of providing a continuously tunable delay range from 0 to 100 ps with minimum 3 dB bandwidth of >20 GHz. By optimizing the width of the waveguide core and the distance between the graphene and the waveguide core, we can obtain the low power consumption and low voltage -length product VπL=1.12 V• cm at 1550 nm when w=2 μm and d=0.3 μm. In addition, the graphene electrode has negligible light absorption with w=2 μm and d=0.3 μm, the switching power is 151 mW without air slots, and the switching power is 95.36 mW with air slots etching depth of 5.3 μm formed on both sides of the waveguides. And further, the air slots formed on both sides and at the bottom of the waveguides make a low switching power of 2.85 mW.

show abstract

“…PTICAL switches play an important role in optical communication and information processing systems, including data centers [1], quantum computing [2] and sensing [3]. To satisfy the ever-increasing demand for compact footprint, low power consumption, and high-speed switching, various kinds of optical switches have been proposed [4][5][6][7][8][9]. These switches can be mainly divided into electro-optic (EO) switch and thermo-optic (TO) switch according to their operation principles.…”

Section: Introductionmentioning

confidence: 99%

Broadband and Low-Random-Phase-Errors 2 × 2 Optical Switch on Thin-Film Lithium Niobate

et al. 2022

View full text Add to dashboard Cite

We propose and demonstrate a broadband and lowrandom-phase-errors 22 optical switch on thin-film lithium niobate platform. The proposed switch is based on a typical Mach-Zehnder interferometer constructed with two 22 3-dB multimode interferometer couplers, two few-mode waveguide (FMW) arms, and corresponding input and output waveguides. The use of FMWs can help to reduce the random phase errors and improve the fabrication tolerances. Over a wide optical bandwidth from 1530 nm to 1605 nm, our typical fabricated switch can work on the desired initial operating state and achieve an extinction ratio mostly larger than ~16 dB. The switching voltage is ~7.3 V. The rise and fall times are 134.4 ns and 8.8 ns, respectively. This work can facilitate the development of optical switches on the lithiumniobate-insulator (LNOI) platform.

show abstract

Low-Power Broadband Thermo-Optic Switch With Weak Polarization Dependence Using a Segmented Graphene Heater

Cited by 21 publications

References 26 publications

Silicon Thermo-Optic Switches with Graphene Heaters Operating at Mid-Infrared Waveband

Silicon Thermo-Optic Switches with Graphene Heaters Operating at Mid-Infrared Waveband

Scalable and Reconfigurable Continuously Tunable Lithium Niobate Thin Film Delay Line Using Graphene Electrodes

Broadband and Low-Random-Phase-Errors 2 × 2 Optical Switch on Thin-Film Lithium Niobate

Contact Info

Product

Resources

About