1. Division of Physics and Applied PhysicsSchool of Physical and Mathematical SciencesNanyang Technological University Singapore 637371 Singapore
2. Hubei Collaborative Innovation Center for Advanced Organic Chemical MaterialsHubei Key Laboratory of Ferro & Piezoelectric Materials and DevicesFaculty of Physics & Electronic SciencesHubei University Wuhan 430062 China
3. Centre for Disruptive Photonic Technologies (CDPT)Nanyang Technological University Singapore 637371 Singapore
4. MajuLabCNRS‐UCA‐SU‐NUS‐NTU International Joint Research Unit Singapore 637371 Singapore