"Exactly," said Dumbledore. "Harry's wand and Voldemorts wand share cores. Each of them contains a feather from the tail of the same phoenix. This phoenix, in fact," he added, and he pointed at the scarlet-and-gold bird, perching peacefully on Harry's knee. (Harry Potter and the Goblet of Fire, Ch 36 - The Parting of the Ways)
Did Voldemort know that his wand's core originated with Fawkes?
If so, when did he find out?
NOTE: I'm asking only about Fawkes. We know that Voldemort found out about the twin cores after he kidnapped Ollivander and tortured that fact out of him.