This is an interesting paper, the article is here: https://interestingengineering.com/physicist-designed-a-plasma-thruster-that-could-make-space-travel-10-times

This is an interesting paper, the article is here: https://interestingengineering.com/physicist-designed-a-plasma-thruster-that-could-make-space-travel-10-times-faster https://interestingengineering.com/physicist-designed-a-plas... The short version is that using a tokamak like structure you can build a device to accelerate plasma, and with that, when you throw it out the back of your rocket, you get thrust. Really high velocity thrust, like 20kM/sec. Depending on the gas used, you could set up some pretty high thrust there. And as a bonus you can throttle it up and down!