29281
By tuning resonator width and charge density , we probe graphene plasmons with lambda p <= lambda 0 / 100 and plasmon resonances as high as 310 meV ( 2500 cm ( - 1 ) ) for 15 nm nanoresonators .
 Chemical: graphene
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: graphene 
Answer:
 Chemical: graphene