Well yeah, a single crystal would be ideal for sound propagation. But what if these crystal-generated waves are transferred to other, less ideal materials?
The quote says 2a is the smallest wavelength possible. Larger wavelength (modes) do exist though. Aren't those less susceptible to...
Alrigh, that is good information! Thanks,
I also found this:
"There is a minimum possible wavelength, given by twice the equilibrium separation a between atoms. As we shall see in the following sections, any wavelength shorter than this can be mapped onto a wavelength longer than 2a, due to the...
I know, theoretically ultrasound has no upper limit (everything above 20kHz).. However, I was wondering whether on a practical note a maximum exists? I read somewhere that frequencies of the order 10^12 Hz were reached. Would a maximum frequency be based on the mean free path between the...