Yes, it can. It provides a feeling of excitement or enthusiasm for whatever you're doing, and can be channeled into working hard for long periods of time. Especially if your job already brings you some satisfaction, then doing your job on amphetamine will provide more. Pilots in the airforce (and possibly other warfighters) are given amphetamine to augment their performance.

I think of it as basically stealing energy or enthusiasm from the future, though. You might feel energized and focused now, but it comes at the expense of less energy and focus when the drug wears off. The withdrawal effect is pretty mild if you take prescription doses of it though, e.g. Adderall (which is amphetamine). At normal moderate doses, taken in the morning, almost all of that energy can be recouped during sleep (though not all). I wouldn't want to take it daily for a long period of time though, otherwise you'll build up an 'energy deficit' that could lead to a crash.

P.S. I know people who have essentially destroyed their lives by becoming addicted to amphetamine or meth. It's a dangerous drug.