PIEZOELECTRIC RESONATOR
An apparatus ( 200 ) comprising: a first electrode ( 204 ), wherein the first electrode comprises at least one layer of graphene; a second electrode ( 208 ); and a layer of piezoelectric material ( 206 ) disposed between the first electrode ( 204 ) and the second electrode ( 208 ), wherein the piezoelectric material ( 206 ) is able to resonate at a resonant frequency in response to application of an oscillating electrical signal to the first or second electrode ( 204, 208 ).
1 - 16 . (canceled)
17 . An apparatus comprising:
a first electrode, wherein the first electrode comprises at least one layer of graphene;
a second electrode; and
a layer of piezoelectric material disposed between the first electrode and the second electrode, wherein the piezoelectric material is able to resonate at a resonant frequency in response to application of an oscillating electrical signal to the first or second electrode.
18 . An apparatus according to claim 17 , wherein the apparatus is configured to change a voltage bias applied to the first electrode.
19 . An apparatus according to claim 17 , wherein the first electrode comprises a single layer of graphene.
20 . An apparatus according to claim 17 , wherein the first electrode comprises multiple layers of graphene.
21 . An apparatus according to claim 17 , wherein the second electrode comprises at least one layer of graphene.
22 . An apparatus according claim 17 , wherein the resonant frequency is a radio frequency.
23 . An apparatus according to claim 17 , wherein the apparatus further comprises a radio frequency signal input and a voltage bias input.
24 . An integrated circuit incorporating the apparatus of claim 17 .
25 . A circuit board including the integrated circuit of claim 24 .
26 . A portable device including apparatus as claimed in claim 17 , the integrated circuit of claim 24 or the circuit board of claim 25 .
27 . A method comprising:
providing a first electrode, wherein the first electrode comprises at least one layer of graphene;
providing a second electrode; and
providing a layer of piezoelectric material disposed between the first electrode and the second electrode, wherein the piezoelectric material is able to resonate at a resonant frequency in response to application of an oscillating electrical signal to the first or second electrode.
28 . A method according to claim 27 , further comprising providing means for changing a voltage bias applied to the first electrode.
29 . A method according to claim 27 , wherein the first electrode comprises a single layer of graphene.
30 . A method according to claim 27 , wherein the first electrode comprises multiple layers of graphene.
31 . A method according to claim 27 , wherein the second electrode comprises at least one layer of graphene.
32 . A method of operating a device, the method comprising:
applying an oscillating electrical signal to apparatus comprising a first electrode, the first electrode comprising at least one layer of graphene, a second electrode, and a layer of piezoelectric material disposed between the first electrode and the second electrode, such as to cause the piezoelectric material to resonate at a resonant frequency; and
changing a bias voltage applied to the apparatus.