Strickland is only the third woman in history to win the physics prize.
Ashkin was awarded half of the Nobel prize for his groundbreaking invention of "optical tweezers" made of lasers that let scientists trap and manipulate tiny organisms and particles in beams of light.
Both inventions had "revolutionized laser physics", the Royal Swedish Academy said. Optical tweezers "created entirely new opportunities for observing and controlling the machinery of life", the Nobel committee said.
"Advanced precision instruments are opening up unexplored areas of research and a multitude of industrial and medical applications", the Nobel organizers wrote on prize's Twitter feed.
In 1987, Ashkin used the tweezers to capture living bacteria without harming them.
Strickland had became attracted to laser physics for not only scientific but also aesthetic reasons: She noticed the green and red beams that shone throughout Mourou's lab like a Christmas tree.
It said the prize of 9 million kronor ($1 million) will be shared one-half by Ashkin and the other half jointly by Mourou and Strickland. They first stretched out the laser pulse in time by several orders of magnitude, thereby reducing their peak power, then passed the stretched pulse through an amplifier, and finally compressed the pulse again in time to produce a short pulse with much enhanced power.
Strickland she said she thought there might have been more than three physics laureates, adding: "Hopefully, in time, it will start to move forward at a faster rate".
USA calls ruling a defeat for Iran, ends treaty
The court's ruling also referred to the 1955 treaty of amity that laid out economic relations between the two countries. Tehran welcomed the ruling by the UN's top court as a "clear sign" that "Iran is in the right".
The science centre introduced a pilot project a year ago that saw women engineers, new to the profession, act as mentors to younger females interested in the profession.
Mourou had been her PhD supervisor.
These became the standard for high-intensity lasers, for example used in millions of corrective eye surgeries per year.
Michael Moloney, head of the American Institute of Physics, praised all the laureates and said, "It is also a personal delight to see Dr. Strickland break the 55-year hiatus since a woman has been awarded a Nobel Prize in physics, making this year's award all the more historic".
"Ultra-sharp laser beams make it possible to cut or drill holes in various materials extremely precisely - even in living matter", the Nobel Prize twitter account noted.
Last year's physics prize went to three Americans who used abstruse theory and ingenious equipment design to detect the faint ripples in the universe called gravitational waves.
The physics prize is the second of the 2018 Nobel Prize awards to be announced, after medicine which was awarded on Monday to two immunologists, James Allison of the USA and Tasuku Honjo of Japan.
There is a Rochester connection to recipients of the Nobel Prize in Physics which was announced on Tuesday. The economics prize will wrap up the Nobel season on Monday, October 8.