There is a design for an ice-melting-slurry-bot that could be made, where the outer diameter of the bore is melted by heat/lasers - where the lasers/heat is also projected into a cone at the point of the bore-ing machine, where the center pipe is a vacuum to slurp up the slurry as it melts the ice around the bore-head...
That would ruin the core samples
/Sci-fi..
My original comment is my idea based on the 1960s patents for nuclear tunnel boring machines which use the reactor heat to exchange the tunnel walls to molten glass... (And I am really into DUMBS - as are many)
https://patents.google.com/patent/US3885832A/en
There are a lot of patents like this - so dont think this line of thought was abandoned, Hello Musk's Boring company... Good thing hes connecting State on a Deep level.