His first deployment to Afghanistan was in 2007.
Lance Corporal Baker joined the army as a medic and was posted to Burnham Regional Support Company in April 2007.
She received a Chief of Army Commendation in 2011 for professionalism and courage in June 2008.
She is the first female New Zealand soldier to be killed in action since troops were sent to the country, and the first woman to be in killed in conflict since nurse Lesley Estelle Cowper of the New Zealand Surgical Team was killed in Vietnam in 1966.
Private Harris joined the NZ Army in February 2009. He had previously deployed to Timor-Leste in 2009/2010.
Defence Force chief Lieutenant General Rhys Jones said the deaths were difficult to deal with so close to the loss of two other soldiers.
"Ours is a dangerous profession, and while we accept these risks the death of colleagues and friends is always difficult to take, particularly coming so close following the 4 August incident where we lost two soldiers.
Lt Gen Jones said the dead soldiers were in the last of a convoy of Humvees taking a soldier with a medical issue for treatment.
They were killed instantly when their Humvee was hit with an improvised explosive device which set off a "massive explosion", Lt Gen Jones said.
The remaining patrol members secured the area and waited for evacuation, he said.
Troops will not leave Afghanistan early - PM
Earlier this morning Prime Minister John Key said New Zealand troops will not be pulled from Afghanistan ahead of schedule.
The attack comes a fortnight after Lance Corporals Pralli Durrer and Rory Malone were killed during a gunfight in the same province.
Mr Key said the Government was still deciding the "exact time'' troops would leave the war-torn country and it was possible it would be early rather than later next year.
"To leave early wouldn't be sensible, it wouldn't be practical and it wouldn't be right,'' Mr Key told TVNZ's Breakfast.
"It's not a simple thing to say we're leaving tomorrow.
"To just turn around this morning and say we're leaving as a result of these three deaths, it wouldn't honour the three people that we've lost ... and it's not the way New Zealand operates.''
Labour Party leader David Shearer said troops should be withdrawn as soon as practically possible.
"We're talking about the end of the year - I would like to think that we could bring that forward,'' he told TV3's Firstline.
Mr Key said the roadside bomb that killed the three soldiers in Bamiyan was "enormous and they would have certainly lost their lives immediately''.
He said intelligence indicated the attack on a convoy travelling north west of Do Abe on the road to Romero was by a new insurgent group that had been targeted for some time.
"It's a dangerous piece of road.''
Jon Stephenson, who is a New Zealand journalist based in Kabul, said violence in Afghanistan had been gaining momentum.
"There is no question that there have been more attacks, that the frequency and severity of those attacks around Bamiyan has increased and that's not surprising because, as a whole, insurgents in Afghanistan seem to be gathering significant momentum,'' he said.
Stephenson said the two primary roads from Kabul to Bamiyan were dangerous.
"I speak regularly to people from Bamiyan who travel from Bamiyan to Kabul and back and they tell me that there are frequently insurgent check points on those roads and that they stop and search vehicles, and occasionally when they find people they think are linked to the Karzai administration they execute those people.''
The deaths overnight bring the total number of New Zealand soldiers killed in Afghanistan to 10.
Defence Minister Jonathan Coleman said the deaths of the three soldiers would come as "a deep shock to the nation''.
Governor-General Lieutenant General Sir Jerry Mateparae said the three soldiers had "brought credit to New Zealand and the New Zealand Defence Force''.
"While serving in war-torn countries such as Afghanistan carries great risks, the deaths of these three soldiers, so soon after the loss of Lance Corporal Pralli Durrer and Lance Corporal Rory Patrick Malone earlier this month, is a great tragedy,'' Sir Jerry said.
NZ fatalities in Afghanistan
August 2012: Three New Zealand soldiers serving with the Provincial Reconstruction Team in Bamyan are killed when their vehicle is hit by an improvised explosive device.
August 2012: PRT Lance Corporals Rory Malone and Pralli Durrer are killed in an ambush in northeast Bamyan Province.
April 2012: PRT Corporal Douglas Hughes dies in incident at Romero.
September 2011: SAS Lance Corporal Leon Smith is killed during an operation in Wardak Province.
August 2011: SAS Corporal Doug Grant, 41, is killed during a Taleban attack in Kabul.
February 2011: PRT Private Kirifi Mila is killed in a Humvee accident in Bamyan.
August 2010: PRT Lieutenant Tim O'Donnell is killed in a firefight after an ambush in Bamyan.
