You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Liquid-Crystalline Blue Phase Laser with Widely Tunable Wavelength. A lasing peak shift of more than 100 nm is realized due to the large shift of a photonic bandgap of a liquid-crystalline blue phase.
{"Chemical": []}