Graphene earphones: entertainment for both humans and animals.
The human hearing range is from 20 Hz to 20 kHz. However, many animals can hear much higher sound frequencies. Dolphins, especially, have a hearing range up to 300 kHz. To our knowledge, there is no data of a reported wide-band sound frequency earphone to satisfy both humans and animals. Here, we show that graphene earphones, packaged into commercial earphone casings can play sounds ranging from 100 Hz to 50 kHz. By using a one-step laser scribing technology, wafer-scale flexible graphene earphones can be obtained in 25 min. Compared with a normal commercial earphone, the graphene earphone has a wider frequency response (100 Hz to 50 kHz) and a three times lower fluctuation (±10 dB). A nonlinear effect exists in the graphene-generated sound frequency spectrum. This effect could be explained by the DC bias added to the input sine waves which may induce higher harmonics. Our numerical calculations show that the sound frequency emitted by graphene could reach up to 1 MHz. In addition, we have demonstrated that a dog wearing a graphene earphone could also be trained and controlled by 35 kHz sound waves. Our results show that graphene could be widely used to produce earphones for both humans and animals.
Institute of Microelectronics and Tsinghua National Laboratory for Information Science and Technology (TNList), Tsinghua University , Beijing 100084, China.
He
H
Tian
Cheng
C
Li
Mohammad Ali
MA
Mohammad
Ya-Long
YL
Cui
Wen-Tian
WT
Mi
Yi
Y
Yang
Dan
D
Xie
Tian-Ling
TL
Ren
D000161:Acoustic Stimulation; D000818:Animals; D004285:Dogs; D004867:Equipment Design; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D007834:Lasers; D008422:Materials Testing; D008962:Models, Theoretical; D036103:Nanotechnology / Q000379:methods*; D009991:Oscillometry; D011312:Pressure; D012815:Signal Processing, Computer-Assisted; D013016:Sound
D006108:Graphite