Cross-polarization Modulation Effect Research Articles

Enhanced ultra-wideband optical frequency comb generation based on cross-polarization modulation effect of semiconductor optical amplifier

Enhanced ultra-wideband optical frequency comb generation based on cross-polarization modulation effect of semiconductor optical amplifier

On-chip all-optical quantizer based on the cross polarization modulation effect in a double-ridge a-Si:H-Si3N4 waveguide.

The on-chip all-optical quantizer is a key functional module to realize all-optical analog-to-digital conversion. It has important applications in future optical communication and ultrafast all-optical signal processing systems. To the best of our knowledge, a novel all-optical quantization scheme based on the cross-polarization modulation effect in a double-ridge a-Si:H-Si3N4 waveguide is proposed. For the optimized waveguide, the maximum nonlinear coefficient and transmission loss at the probe wavelength are 2680.5m-1W-1 and 2.246 dB/cm, respectively. The simulation results of the proposed all-optical quantizer show that a nonlinear phase shift of 8 can be generated in the 8.79 mm long waveguide when the peak pump light power is 0.8 W. A 16-level quantization and a 4-bit quantization resolution are obtained. The effective number of bits is 3.79-bit, which is only 0.21-bit away from the ideal resolution.

Design analysis and applications of all-optical multifunctional logic using a semiconductor optical amplifier-based polarization rotation switch

In this communication, a new semiconductor optical amplifier (SOA)-based module for multi-valued logic units using the cross-polarization modulation effect is proposed and analyzed. The design is simple and compact, consisting of only three SOAs and a few passive optical elements. SOAs have very low switching power (< 1mW), and are very small (< 1 mm) and integrable into modern optical integrated circuits. Being multifunctional, the design is versatile; it can function as a demultiplexer, comparator, half adder, half subtractor, and as basic (OR, AND), universal (NOR, NAND), XOR, and XNOR logic gates. This design follows a tree architecture, operates at very high speed (~ 100Gbit/s), and provides a good Q factor (30 dB or more). The corresponding bit error rate (BER) is very low (~ 10–24). In this work, a relative eye opening as large as 90.4% is calculated. The variations in Q and BER with noise and control power are also investigated.

Design of optical wavelength conversion based on cross polarization modulation effect of SOA-MZI

In this paper, the all optical up and down wavelength converter based on cross polarization modulation (XPolM) effect in semiconductor optical amplifier Mach–Zehnder Interferometer (SOA-MZI) has been proposed and evaluated for error free operation to show the feasibility of 40 Gbps differential phase shift keying modulated data signal. The wavelength conversion is achieved by rotational state of polarization of pump and probe signal in SOA. Also, investigation of wavelength converter is theoretically and analytically validated for optimum performance and investigation results show good agreement with each other. The impact of variable signal power along with different parameter of SOA on performance of converted wavelength signal in terms of optical received power and Q-factor has been given. The investigations revealed that wavelength converter based on XPolM effect in SOA-MZI can be the promising option to enhance the expandability and accessibility of future hybrid optical access networks.

All-optical generation of binary phase-coded microwave signal based on cross-polarization modulation in a highly nonlinear fiber

We report a novel all-optical approach to generate a binary phase-coded microwave signal based on a cross-polarization modulation effect in a highly nonlinear fiber. The carrier frequency of the binary phase-coded microwave signal is widely tunable. Moreover, the precise π phase shift of the microwave signal is independent of the optical power of the control beam. The proposed approach is theoretically analyzed and experimentally verified. For a proof-of-concept demonstration, the binary phase-coded microwave signals with a carrier frequency of 20GHz at a coding rate of 5 Gb/s and with a carrier frequency of 30GHz at a coding rate of 7.5 Gb/s are experimentally generated. The pulse compression capability of the system is also evaluated. The measured and simulated results fit well with each other.

Broadband photonic single sideband frequency up-converter based on the cross polarization modulation effect in a semiconductor optical amplifier for radio-over-fiber systems

A broadband photonic single sideband (SSB) frequency up-converter based on the cross polarization modulation (XPolM) effect in a semiconductor optical amplifier (SOA) is proposed and experimentally demonstrated. An optical radio frequency (RF) signal in the form of an optical single sideband (OSSB) is generated by the photonic SSB frequency up-converter to solve the power fading problem caused by fiber chromatic dispersion. The generated OSSB RF signal has almost identical optical carrier power and optical sideband power. This SSB frequency up-conversion scheme shows an almost flat electrical RF power response as a function of the RF frequency in a range from 31 GHz to 75 GHz after 40 km single mode fiber (SMF) transmission. The photonic SSB frequency up-conversion technique shows negligible phase noise degradation. The phase noise of the up-converted RF signal at 49 GHz for an offset of 10 kHz is -93.17 dBc/Hz. Linearity analysis shows that the photonic SSB frequency up-converter has a spurious free dynamic range (SFDR) value of 79.51 dB · Hz(2/3).

Ultrawideband pulse generation and bipolar coding based on optical cross-polarization modulation in highly nonlinear photonic crystal fiber

A novel optical method for ultrawideband (UWB) monocycle pulse generation and bipolar coding is proposed and experimentally demonstrated. The proposed scheme is based on the cross-polarization modulation effect in highly nonlinear photonic crystal fiber (HNPCF). The monocycle pulse with a time duration of 84 ps is generated, and four groups of bipolar codes are obtained.

UWB monocycle pulse generation based on optical cross-polarization modulation

A novel all-optical method for ultra-wideband (UWB) monocycle pulses generation based on cross polarization modulation (CPM) effect in highly nonlinear photonic crystal fiber is proposed and demonstrated. Due to the CPM effect between the probe light and the pump pulse, a pair of polarity-reversed Gaussian pulses is produced. After proper differential delay, an UWB monocycle pulse with 84-ps width and the fractional bandwidth of 153% is generated after photodetection.

All-Optical AND Logic Gate without Additional Input Beam by Utilizing Cross Polarization Modulation Effect

A novel design of all-optical AND gate is proposed by using cross polarization modulation effect in a semiconductor optical amplifier. In this scheme, an additional continuous-wave beam is not required as that in traditional scheme. AND output is obtained on either of two input signal wavelengths. The AND scheme is numerically simulated and experimentally demonstrated at a bit rate of 10 Gb/s successfully.

All-optical dual-wavelength conversion based on cross-polarization modulation and its application to format conversion from amplitude-shift keying to frequency-shift keying

Simultaneous noninverted and inverted dual-wavelength conversion is proposed and demonstrated by using a cross-polarization modulation effect in a semiconductor optical amplifier (SOA). Experiments show that noninverted and inverted conversions lead to power penalties of 1.3 dB and 0.8 dB, respectively, at a bit rate of 10 Gb/s. Based on this scheme, we have demonstrated, for the first time to our knowledge, an all-optical modulation format conversion from amplitude-shift keying (ASK) to frequency-shift keying (FSK). A frequency-shift keying signal with flexible tone spacing and high bit rate can be successfully generated by using this method.

Photonic microwave notch filter using cross polarization modulation in highly nonlinear fiber and polarization-dependent optical delay in high birefringence fiber

A novel photonic microwave notch filter with both negative and positive coefficients is proposed and demonstrated using a single optical source. These coefficients are generated in a highly nonlinear fiber by cross polarization modulation effect and guided through a high birefringence fiber, and finally detected. Due to the orthogonal polarity between the two coefficients, the proposed filter has a stable transfer response and no resonance peaks at baseband. The experimental results showed a stable notch filter characteristic with the free spectral range of 3.97 GHz over the range of 15 GHz.

5-Gb/s XOR optical gate based on cross-polarization modulation in semiconductor optical amplifiers

We demonstrate a new design for a XOR optical gate operating in the GHz regime using the cross-polarization modulation effect in a semiconductor optical amplifier. Dynamic and optically controlled polarization rotation in the devices is used to control the output power of the device. Static extinction ratio of the order of 20 dB can be obtained. Bit rate doubling at rate of 1.2 and 2.5 Gb/s have been demonstrated.