Investigation of electrooptic modulator disruption by microwave-induced transients

Area of Science:

• Photonics
• Materials Science
• Electrical Engineering

Background:

• Lithium niobate electrooptic modulators are critical components in photonic systems.
• Radio frequency (RF) pulses can cause disruption and damage to these modulators.
• Understanding the underlying physical mechanisms is essential for reliable device operation.

Purpose of the Study:

• To investigate the physical mechanisms behind RF pulse-induced disruption of lithium niobate electrooptic modulators.
• To identify the role of resistive heating in modulator disruption and damage.
• To propose mitigation strategies for RF-induced effects.

Main Methods:

• Detailed physical investigation of modulator disruption.
• Analysis of resistive heating in coplanar waveguide electrodes.
• Examination of thermo-optic effects on optical phase shifts.
• Correlation of RF power levels with modulator damage.

Main Results:

• Short-term modulator disruption is caused by resistive heating in the electrode's metal conductor.
• This heating induces a thermo-optic phase shift in the modulator's waveguides.
• Higher RF power levels lead to permanent modulator damage due to resistive heating.
• Improved thermal management can mitigate short-term RF disruption and potential damage.

Conclusions:

• Resistive heating is the primary mechanism for RF pulse-induced disruption in lithium niobate modulators.
• Thermal management is crucial for enhancing modulator resilience.
• Phase modulated photonic links offer a potential solution to reduce or eliminate disruption.