北京清华大学的姜开利与同事发现,当碳纳米管薄膜通以交流电时会发出声音。这源自一种热声效应,交变电流会周期性地加热薄膜产生温度变化,随即在空气中出现周期性压力变化,发出响声。他们用碳纳米管制成的新型扬声器,仅有几 Jiang, Tsinghua University, Beijing, and colleagues found that carbon nanotubes make a noise when they pass through alternating current. This is due to a thermoacoustic effect, which causes the alternating current to periodically heat the film to produce a temperature change, followed by periodic pressure changes in the air, producing a loud sound. The new speakers made of carbon nanotubes are just a few